The type implementing this traversable
The type implementing this traversable
A class supporting filtered operations.
Test two objects for inequality.
Test two objects for inequality.
true
if !(this == that), false otherwise.
Equivalent to x.hashCode
except for boxed numeric types and null
.
Equivalent to x.hashCode
except for boxed numeric types and null
.
For numerics, it returns a hash value which is consistent
with value equality: if two value type instances compare
as true, then ## will produce the same hash value for each
of them.
For null
returns a hashcode where null.hashCode
throws a
NullPointerException
.
a hash value consistent with ==
Creates a new collection containing both the elements of this collection and the provided traversable object.
Creates a new collection containing both the elements of this collection and the provided traversable object.
the traversable object.
a new collection consisting of all the elements of this collection and xs
.
(Changed in version 2.8.0) ++
creates a new buffer. Use ++=
to add an element from this buffer and return that buffer itself.
[use case] Returns a new list buffer containing the elements from the left hand operand followed by the elements from the right hand operand.
Returns a new list buffer containing the elements from the left hand operand followed by the elements from the right hand operand. The element type of the list buffer is the most specific superclass encompassing the element types of the two operands.
Example:
scala> val a = LinkedList(1) a: scala.collection.mutable.LinkedList[Int] = LinkedList(1) scala> val b = LinkedList(2) b: scala.collection.mutable.LinkedList[Int] = LinkedList(2) scala> val c = a ++ b c: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2) scala> val d = LinkedList('a') d: scala.collection.mutable.LinkedList[Char] = LinkedList(a) scala> val e = c ++ d e: scala.collection.mutable.LinkedList[AnyVal] = LinkedList(1, 2, a)
the element type of the returned collection.
the traversable to append.
a new list buffer which contains all elements of this list buffer
followed by all elements of that
.
As with ++
, returns a new collection containing the elements from the
left operand followed by the elements from the right operand.
As with ++
, returns a new collection containing the elements from the
left operand followed by the elements from the right operand.
It differs from ++
in that the right operand determines the type of
the resulting collection rather than the left one.
Mnemonic: the COLon is on the side of the new COLlection type.
Example:
scala> val x = List(1) x: List[Int] = List(1) scala> val y = LinkedList(2) y: scala.collection.mutable.LinkedList[Int] = LinkedList(2) scala> val z = x ++: y z: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2)
This overload exists because: for the implementation of ++:
we should
reuse that of ++
because many collections override it with more
efficient versions.
Since TraversableOnce
has no ++
method, we have to implement that
directly, but Traversable
and down can use the overload.
the element type of the returned collection.
the class of the returned collection. In the standard library configuration,
That
is always ListBuffer[B]
because an implicit of type CanBuildFrom[ListBuffer, B, ListBuffer[B]]
is defined in object ListBuffer
.
the traversable to append.
an implicit value of class CanBuildFrom
which determines the
result class That
from the current representation type Repr
and the new element type B
. This is usually the canBuildFrom
value
defined in object ListBuffer
.
a new collection of type That
which contains all elements
of this list buffer followed by all elements of that
.
[use case] As with ++
, returns a new collection containing the elements from the left operand followed by the
elements from the right operand.
As with ++
, returns a new collection containing the elements from the left operand followed by the
elements from the right operand.
It differs from ++
in that the right operand determines the type of
the resulting collection rather than the left one.
Mnemonic: the COLon is on the side of the new COLlection type.
Example:
scala> val x = List(1) x: List[Int] = List(1) scala> val y = LinkedList(2) y: scala.collection.mutable.LinkedList[Int] = LinkedList(2) scala> val z = x ++: y z: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2)
the element type of the returned collection.
the traversable to append.
a new list buffer which contains all elements of this list buffer
followed by all elements of that
.
Appends all elements produced by a TraversableOnce to this list buffer.
Appends all elements produced by a TraversableOnce to this list buffer.
the TraversableOnce producing the elements to append.
the list buffer itself.
Prepends elements to this buffer.
Prepends elements to this buffer.
the TraversableOnce containing the elements to prepend.
the buffer itself.
[use case] A copy of the list buffer with an element prepended.
A copy of the list buffer with an element prepended.
Note that :-ending operators are right associative (see example).
A mnemonic for +:
vs. :+
is: the COLon goes on the COLlection side.
Also, the original list buffer is not modified, so you will want to capture the result.
Example:
scala> val x = LinkedList(1) x: scala.collection.mutable.LinkedList[Int] = LinkedList(1) scala> val y = 2 +: x y: scala.collection.mutable.LinkedList[Int] = LinkedList(2, 1) scala> println(x) LinkedList(1)
the prepended element
a new list buffer consisting of elem
followed
by all elements of this list buffer.
Appends a single element to this buffer.
Appends a single element to this buffer. This operation takes constant time.
the element to append.
this list buffer.
Appends two or more elements to this list buffer.
Appends two or more elements to this list buffer.
the first element to append.
the second element to append.
the remaining elements to append.
the list buffer itself
Prepends a single element to this buffer.
Prepends a single element to this buffer. This operation takes constant time.
the element to prepend.
this list buffer.
Creates a new collection with all the elements of this collection except the two or more specified elements.
Creates a new collection with all the elements of this collection except the two or more specified elements.
the first element to remove.
the second element to remove.
the remaining elements to remove.
a new collection consisting of all the elements of this collection except
elem1
, elem2
and those in elems
.
(Changed in version 2.8.0) -
creates a new buffer. Use -=
to remove an element from this buffer and return that buffer itself.
Creates a new collection with all the elements of this collection except elem
.
Creates a new collection with all the elements of this collection except elem
.
the element to remove.
a new collection consisting of all the elements of this collection except elem
.
(Changed in version 2.8.0) -
creates a new buffer. Use -=
to remove an element from this buffer and return that buffer itself.
Creates a new collection with all the elements of this collection except those provided by the specified traversable object.
Creates a new collection with all the elements of this collection except those provided by the specified traversable object.
the traversable object.
a new collection with all the elements of this collection except
those in xs
(Changed in version 2.8.0) --
creates a new buffer. Use --=
to remove an element from this buffer and return that buffer itself.
Removes all elements produced by an iterator from this list buffer.
Removes all elements produced by an iterator from this list buffer.
the iterator producing the elements to remove.
the list buffer itself
Remove a single element from this buffer.
Remove a single element from this buffer. May take time linear in the buffer size.
the element to remove.
this list buffer.
Removes two or more elements from this list buffer.
Removes two or more elements from this list buffer.
the first element to remove.
the second element to remove.
the remaining elements to remove.
the list buffer itself
Applies a binary operator to a start value and all elements of this list buffer, going left to right.
Applies a binary operator to a start value and all elements of this list buffer, going left to right.
Note: /:
is alternate syntax for foldLeft
; z /: xs
is the same as
xs foldLeft z
.
Examples:
Note that the folding function used to compute b is equivalent to that used to compute c.
scala> val a = LinkedList(1,2,3,4) a: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4) scala> val b = (5 /: a)(_+_) b: Int = 15 scala> val c = (5 /: a)((x,y) => x + y) c: Int = 15
the result type of the binary operator.
the start value.
the binary operator.
the result of inserting op
between consecutive elements of this list buffer,
going left to right with the start value z
on the left:
op(...op(op(z, x_1), x_2), ..., x_n)
where x1, ..., xn
are the elements of this list buffer.
[use case] A copy of this list buffer with an element appended.
A copy of this list buffer with an element appended.
A mnemonic for +:
vs. :+
is: the COLon goes on the COLlection side.
Example:
scala> import scala.collection.mutable.LinkedList import scala.collection.mutable.LinkedList scala> val a = LinkedList(1) a: scala.collection.mutable.LinkedList[Int] = LinkedList(1) scala> val b = a :+ 2 b: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2) scala> println(a) LinkedList(1)
the appended element
a new list buffer consisting of
all elements of this list buffer followed by elem
.
Applies a binary operator to all elements of this list buffer and a start value, going right to left.
Applies a binary operator to all elements of this list buffer and a start value, going right to left.
Note: :\
is alternate syntax for foldRight
; xs :\ z
is the same as
xs foldRight z
.
Examples:
Note that the folding function used to compute b is equivalent to that used to compute c.
scala> val a = LinkedList(1,2,3,4) a: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4) scala> val b = (a :\ 5)(_+_) b: Int = 15 scala> val c = (a :\ 5)((x,y) => x + y) c: Int = 15
the result type of the binary operator.
the start value
the binary operator
the result of inserting op
between consecutive elements of this list buffer,
going right to left with the start value z
on the right:
op(x_1, op(x_2, ... op(x_n, z)...))
where x1, ..., xn
are the elements of this list buffer.
Send a message to this scriptable object.
Send a message to this scriptable object.
the message to send.
Test two objects for equality.
Test two objects for equality.
The expression x == that
is equivalent to if (x eq null) that eq null else x.equals(that)
.
true
if the receiver object is equivalent to the argument; false
otherwise.
Appends all elements of this list buffer to a string builder.
Appends all elements of this list buffer to a string builder.
The written text consists of the string representations (w.r.t. the method
toString
) of all elements of this list buffer without any separator string.
Example:
scala> val a = LinkedList(1,2,3,4) a: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4) scala> val b = new StringBuilder() b: StringBuilder = scala> val h = a.addString(b) b: StringBuilder = 1234
the string builder to which elements are appended.
the string builder b
to which elements were appended.
Appends all elements of this list buffer to a string builder using a separator string.
Appends all elements of this list buffer to a string builder using a separator string.
The written text consists of the string representations (w.r.t. the method toString
)
of all elements of this list buffer, separated by the string sep
.
Example:
scala> val a = LinkedList(1,2,3,4) a: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4) scala> val b = new StringBuilder() b: StringBuilder = scala> a.addString(b, ", ") res0: StringBuilder = 1, 2, 3, 4
the string builder to which elements are appended.
the separator string.
the string builder b
to which elements were appended.
Appends all elements of this list buffer to a string builder using start, end, and separator strings.
Appends all elements of this list buffer to a string builder using start, end, and separator strings.
The written text begins with the string start
and ends with the string end
.
Inside, the string representations (w.r.t. the method toString
)
of all elements of this list buffer are separated by the string sep
.
Example:
scala> val a = LinkedList(1,2,3,4) a: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4) scala> val b = new StringBuilder() b: StringBuilder = scala> a.addString(b, "LinkedList(", ", ", ")") res1: StringBuilder = LinkedList(1, 2, 3, 4)
the string builder to which elements are appended.
the starting string.
the separator string.
the ending string.
the string builder b
to which elements were appended.
Aggregates the results of applying an operator to subsequent elements.
Aggregates the results of applying an operator to subsequent elements.
This is a more general form of fold
and reduce
. It has similar
semantics, but does not require the result to be a supertype of the
element type. It traverses the elements in different partitions
sequentially, using seqop
to update the result, and then applies
combop
to results from different partitions. The implementation of
this operation may operate on an arbitrary number of collection
partitions, so combop
may be invoked an arbitrary number of times.
For example, one might want to process some elements and then produce
a Set
. In this case, seqop
would process an element and append it
to the list, while combop
would concatenate two lists from different
partitions together. The initial value z
would be an empty set.
pc.aggregate(Set[Int]())(_ += process(_), _ ++ _)
Another example is calculating geometric mean from a collection of doubles (one would typically require big doubles for this).
the type of accumulated results
the initial value for the accumulated result of the partition - this
will typically be the neutral element for the seqop
operator (e.g.
Nil
for list concatenation or 0
for summation)
an operator used to accumulate results within a partition
an associative operator used to combine results from different partitions
Composes this partial function with a transformation function that gets applied to results of this partial function.
Composes this partial function with a transformation function that gets applied to results of this partial function.
the result type of the transformation function.
the transformation function
a partial function with the same domain as this partial function, which maps
arguments x
to k(this(x))
.
Appends the given elements to this buffer.
Appends the given elements to this buffer.
the elements to append.
Appends the elements contained in a traversable object to this buffer.
Appends the elements contained in a traversable object to this buffer.
the traversable object containing the elements to append.
Selects an element by its index in the list buffer.
Selects an element by its index in the list buffer.
Example:
scala> val x = LinkedList(1, 2, 3, 4, 5) x: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4, 5) scala> x(3) res1: Int = 4
the element of this list buffer at index idx
, where 0
indicates the first element.
if idx
does not satisfy 0 <= idx < length
.
Applies this partial function to the given argument when it is contained in the function domain.
Applies this partial function to the given argument when it is contained in the function domain. Applies fallback function where this partial function is not defined.
Note that expression pf.applyOrElse(x, default)
is equivalent to
if(pf isDefinedAt x) pf(x) else default(x)
except that applyOrElse
method can be implemented more efficiently.
For all partial function literals compiler generates applyOrElse
implementation which
avoids double evaluation of pattern matchers and guards.
This makes applyOrElse
the basis for the efficient implementation for many operations and scenarios, such as:
orElse
/andThen
chains does not lead to
excessive apply
/isDefinedAt
evaluationlift
and unlift
do not evaluate source functions twice on each invocationrunWith
allows efficient imperative-style combining of partial functions
with conditionally applied actions For non-literal partial function classes with nontrivial isDefinedAt
method
it is recommended to override applyOrElse
with custom implementation that avoids
double isDefinedAt
evaluation. This may result in better performance
and more predictable behavior w.r.t. side effects.
the function argument
the fallback function
the result of this function or fallback function application.
2.10
Cast the receiver object to be of type T0
.
Cast the receiver object to be of type T0
.
Note that the success of a cast at runtime is modulo Scala's erasure semantics.
Therefore the expression 1.asInstanceOf[String]
will throw a ClassCastException
at
runtime, while the expression List(1).asInstanceOf[List[String]]
will not.
In the latter example, because the type argument is erased as part of compilation it is
not possible to check whether the contents of the list are of the requested type.
the receiver object.
if the receiver object is not an instance of the erasure of type T0
.
Method called from equality methods, so that user-defined subclasses can refuse to be equal to other collections of the same kind.
Method called from equality methods, so that user-defined subclasses can refuse to be equal to other collections of the same kind.
The object with which this list buffer should be compared
true
, if this list buffer can possibly equal that
, false
otherwise. The test
takes into consideration only the run-time types of objects but ignores their elements.
Clears the buffer contents.
Clears the buffer contents.
Returns a clone of this buffer.
Returns a clone of this buffer.
a ListBuffer
with the same elements.
[use case] Builds a new collection by applying a partial function to all elements of this list buffer on which the function is defined.
Builds a new collection by applying a partial function to all elements of this list buffer on which the function is defined.
the element type of the returned collection.
the partial function which filters and maps the list buffer.
a new list buffer resulting from applying the given partial function
pf
to each element on which it is defined and collecting the results.
The order of the elements is preserved.
Finds the first element of the list buffer for which the given partial function is defined, and applies the partial function to it.
Finds the first element of the list buffer for which the given partial function is defined, and applies the partial function to it.
the partial function
an option value containing pf applied to the first
value for which it is defined, or None
if none exists.
Seq("a", 1, 5L).collectFirst({ case x: Int => x*10 }) = Some(10)
Iterates over combinations.
Iterates over combinations.
An Iterator which traverses the possible n-element combinations of this list buffer.
"abbbc".combinations(2) = Iterator(ab, ac, bb, bc)
The factory companion object that builds instances of class ListBuffer
.
The factory companion object that builds instances of class ListBuffer
.
(or its Iterable
superclass where class ListBuffer
is not a Seq
.)
Composes two instances of Function1 in a new Function1, with this function applied last.
Composes two instances of Function1 in a new Function1, with this function applied last.
the type to which function g
can be applied
a function A => T1
a new function f
such that f(x) == apply(g(x))
Tests whether this list buffer contains a given value as an element.
Tests whether this list buffer contains a given value as an element.
the element to test.
true
if this list buffer has an element that is equal (as
determined by ==
) to elem
, false
otherwise.
Tests whether this list buffer contains a given sequence as a slice.
Tests whether this list buffer contains a given sequence as a slice.
the sequence to test
true
if this list buffer contains a slice with the same elements
as that
, otherwise false
.
[use case] Copies values of this list buffer to an array.
Copies values of this list buffer to an array.
Fills the given array xs
with values of this list buffer.
Copying will stop once either the end of the current list buffer is reached,
or the end of the array is reached.
the array to fill.
[use case] Copies values of this list buffer to an array.
Copies values of this list buffer to an array.
Fills the given array xs
with values of this list buffer, beginning at index start
.
Copying will stop once either the end of the current list buffer is reached,
or the end of the array is reached.
the array to fill.
the starting index.
[use case] Copies elements of this list buffer to an array.
Copies elements of this list buffer to an array.
Fills the given array xs
with at most len
elements of
this list buffer, starting at position start
.
Copying will stop once either the end of the current list buffer is reached,
or the end of the array is reached, or len
elements have been copied.
the array to fill.
the starting index.
the maximal number of elements to copy.
Copies all elements of this list buffer to a buffer.
Copies all elements of this list buffer to a buffer.
The buffer to which elements are copied.
Tests whether every element of this list buffer relates to the corresponding element of another sequence by satisfying a test predicate.
Tests whether every element of this list buffer relates to the corresponding element of another sequence by satisfying a test predicate.
the type of the elements of that
the other sequence
the test predicate, which relates elements from both sequences
true
if both sequences have the same length and
p(x, y)
is true
for all corresponding elements x
of this list buffer
and y
of that
, otherwise false
.
Counts the number of elements in the list buffer which satisfy a predicate.
Counts the number of elements in the list buffer which satisfy a predicate.
the predicate used to test elements.
the number of elements satisfying the predicate p
.
[use case] Computes the multiset difference between this list buffer and another sequence.
Computes the multiset difference between this list buffer and another sequence.
the sequence of elements to remove
a new list buffer which contains all elements of this list buffer
except some of occurrences of elements that also appear in that
.
If an element value x
appears
n times in that
, then the first n occurrences of x
will not form
part of the result, but any following occurrences will.
Builds a new list buffer from this list buffer without any duplicate elements.
Builds a new list buffer from this list buffer without any duplicate elements.
A new list buffer which contains the first occurrence of every element of this list buffer.
Selects all elements except first n ones.
Selects all elements except first n ones.
the number of elements to drop from this list buffer.
a list buffer consisting of all elements of this list buffer except the first n
ones, or else the
empty list buffer, if this list buffer has less than n
elements.
Selects all elements except last n ones.
Selects all elements except last n ones.
The number of elements to take
a list buffer consisting of all elements of this list buffer except the last n
ones, or else the
empty list buffer, if this list buffer has less than n
elements.
Drops longest prefix of elements that satisfy a predicate.
Drops longest prefix of elements that satisfy a predicate.
the longest suffix of this list buffer whose first element
does not satisfy the predicate p
.
Tests whether this list buffer ends with the given sequence.
Tests whether this list buffer ends with the given sequence.
the sequence to test
true
if this list buffer has that
as a suffix, false
otherwise.
Tests whether the argument (arg0
) is a reference to the receiver object (this
).
Tests whether the argument (arg0
) is a reference to the receiver object (this
).
The eq
method implements an equivalence relation on
non-null instances of AnyRef
, and has three additional properties:
x
and y
of type AnyRef
, multiple invocations of
x.eq(y)
consistently returns true
or consistently returns false
.x
of type AnyRef
, x.eq(null)
and null.eq(x)
returns false
.null.eq(null)
returns true
. When overriding the equals
or hashCode
methods, it is important to ensure that their behavior is
consistent with reference equality. Therefore, if two objects are references to each other (o1 eq o2
), they
should be equal to each other (o1 == o2
) and they should hash to the same value (o1.hashCode == o2.hashCode
).
true
if the argument is a reference to the receiver object; false
otherwise.
The equals method for arbitrary sequences.
The equals method for arbitrary sequences. Compares this sequence to some other object.
The object to compare the sequence to
true
if that
is a sequence that has the same elements as
this sequence in the same order, false
otherwise
Tests whether a predicate holds for some of the elements of this list buffer.
Tests whether a predicate holds for some of the elements of this list buffer.
the predicate used to test elements.
true
if the given predicate p
holds for some of the
elements of this list buffer, otherwise false
.
Selects all elements of this list buffer which satisfy a predicate.
Selects all elements of this list buffer which satisfy a predicate.
the predicate used to test elements.
a new list buffer consisting of all elements of this list buffer that satisfy the given
predicate p
. The order of the elements is preserved.
Selects all elements of this list buffer which do not satisfy a predicate.
Selects all elements of this list buffer which do not satisfy a predicate.
the predicate used to test elements.
a new list buffer consisting of all elements of this list buffer that do not satisfy the given
predicate p
. The order of the elements is preserved.
Called by the garbage collector on the receiver object when there are no more references to the object.
Called by the garbage collector on the receiver object when there are no more references to the object.
The details of when and if the finalize
method is invoked, as
well as the interaction between finalize
and non-local returns
and exceptions, are all platform dependent.
Finds the first element of the list buffer satisfying a predicate, if any.
Finds the first element of the list buffer satisfying a predicate, if any.
the predicate used to test elements.
an option value containing the first element in the list buffer
that satisfies p
, or None
if none exists.
[use case] Builds a new collection by applying a function to all elements of this list buffer and using the elements of the resulting collections.
Builds a new collection by applying a function to all elements of this list buffer and using the elements of the resulting collections.
For example:
def getWords(lines: Seq[String]): Seq[String] = lines flatMap (line => line split "\\W+")
The type of the resulting collection is guided by the static type of list buffer. This might cause unexpected results sometimes. For example:
// lettersOf will return a Seq[Char] of likely repeated letters, instead of a Set def lettersOf(words: Seq[String]) = words flatMap (word => word.toSet) // lettersOf will return a Set[Char], not a Seq def lettersOf(words: Seq[String]) = words.toSet flatMap (word => word.toSeq) // xs will be a an Iterable[Int] val xs = Map("a" -> List(11,111), "b" -> List(22,222)).flatMap(_._2) // ys will be a Map[Int, Int] val ys = Map("a" -> List(1 -> 11,1 -> 111), "b" -> List(2 -> 22,2 -> 222)).flatMap(_._2)
the element type of the returned collection.
the function to apply to each element.
a new list buffer resulting from applying the given collection-valued function
f
to each element of this list buffer and concatenating the results.
[use case] Converts this list buffer of traversable collections into a list buffer formed by the elements of these traversable collections.
Converts this list buffer of traversable collections into a list buffer formed by the elements of these traversable collections.
The resulting collection's type will be guided by the static type of list buffer. For example:
val xs = List(Set(1, 2, 3), Set(1, 2, 3)) // xs == List(1, 2, 3, 1, 2, 3) val ys = Set(List(1, 2, 3), List(3, 2, 1)) // ys == Set(1, 2, 3)
the type of the elements of each traversable collection.
a new list buffer resulting from concatenating all element list buffers.
Folds the elements of this list buffer using the specified associative binary operator.
Folds the elements of this list buffer using the specified associative binary operator.
The order in which operations are performed on elements is unspecified and may be nondeterministic.
a type parameter for the binary operator, a supertype of A
.
a neutral element for the fold operation; may be added to the result
an arbitrary number of times, and must not change the result (e.g., Nil
for list concatenation,
0 for addition, or 1 for multiplication.)
a binary operator that must be associative
the result of applying fold operator op
between all the elements and z
Applies a binary operator to a start value and all elements of this list buffer, going left to right.
Applies a binary operator to a start value and all elements of this list buffer, going left to right.
the result type of the binary operator.
the start value.
the binary operator.
the result of inserting op
between consecutive elements of this list buffer,
going left to right with the start value z
on the left:
op(...op(z, x_1), x_2, ..., x_n)
where x1, ..., xn
are the elements of this list buffer.
Applies a binary operator to all elements of this list buffer and a start value, going right to left.
Applies a binary operator to all elements of this list buffer and a start value, going right to left.
the result type of the binary operator.
the start value.
the binary operator.
the result of inserting op
between consecutive elements of this list buffer,
going right to left with the start value z
on the right:
op(x_1, op(x_2, ... op(x_n, z)...))
where x1, ..., xn
are the elements of this list buffer.
Tests whether a predicate holds for all elements of this list buffer.
Tests whether a predicate holds for all elements of this list buffer.
the predicate used to test elements.
true
if the given predicate p
holds for all elements
of this list buffer, otherwise false
.
[use case]
the function that is applied for its side-effect to every element.
The result of function f
is discarded.
Returns string formatted according to given format
string.
Returns string formatted according to given format
string.
Format strings are as for String.format
(@see java.lang.String.format).
The generic builder that builds instances of ListBuffer
at arbitrary element types.
The generic builder that builds instances of ListBuffer
at arbitrary element types.
A representation that corresponds to the dynamic class of the receiver object.
A representation that corresponds to the dynamic class of the receiver object.
The nature of the representation is platform dependent.
a representation that corresponds to the dynamic class of the receiver object.
not specified by SLS as a member of AnyRef
Partitions this list buffer into a map of list buffers according to some discriminator function.
Partitions this list buffer into a map of list buffers according to some discriminator function.
Note: this method is not re-implemented by views. This means when applied to a view it will always force the view and return a new list buffer.
the type of keys returned by the discriminator function.
the discriminator function.
A map from keys to list buffers such that the following invariant holds:
(xs partition f)(k) = xs filter (x => f(x) == k)
That is, every key k
is bound to a list buffer of those elements x
for which f(x)
equals k
.
Partitions elements in fixed size list buffers.
Partitions elements in fixed size list buffers.
the number of elements per group
An iterator producing list buffers of size size
, except the
last will be truncated if the elements don't divide evenly.
scala.collection.Iterator, method grouped
Tests whether this list buffer is known to have a finite size.
Tests whether this list buffer is known to have a finite size.
All strict collections are known to have finite size. For a non-strict
collection such as Stream
, the predicate returns true
if all
elements have been computed. It returns false
if the stream is
not yet evaluated to the end.
Note: many collection methods will not work on collections of infinite sizes.
true
if this collection is known to have finite size,
false
otherwise.
Hashcodes for ListBuffer
produce a value from the hashcodes of all the
elements of the list buffer.
Hashcodes for ListBuffer
produce a value from the hashcodes of all the
elements of the list buffer.
the hash code value for this object.
Selects the first element of this list buffer.
Selects the first element of this list buffer.
the first element of this list buffer.
if the list buffer is empty.
Optionally selects the first element.
Optionally selects the first element.
the first element of this list buffer if it is nonempty,
None
if it is empty.
[use case] Finds index of first occurrence of some value in this list buffer after or at some start index.
Finds index of first occurrence of some value in this list buffer after or at some start index.
the element value to search for.
the start index
the index >= from
of the first element of this list buffer that is equal (as determined by ==
)
to elem
, or -1
, if none exists.
[use case] Finds index of first occurrence of some value in this list buffer.
Finds index of first occurrence of some value in this list buffer.
the element value to search for.
the index of the first element of this list buffer that is equal (as determined by ==
)
to elem
, or -1
, if none exists.
Finds first index after or at a start index where this list buffer contains a given sequence as a slice.
Finds first index after or at a start index where this list buffer contains a given sequence as a slice.
the sequence to test
the start index
the first index >= from
such that the elements of this list buffer starting at this index
match the elements of sequence that
, or -1
of no such subsequence exists.
Finds first index where this list buffer contains a given sequence as a slice.
Finds first index where this list buffer contains a given sequence as a slice.
the sequence to test
the first index such that the elements of this list buffer starting at this index
match the elements of sequence that
, or -1
of no such subsequence exists.
Finds index of the first element satisfying some predicate after or at some start index.
Finds index of the first element satisfying some predicate after or at some start index.
the predicate used to test elements.
the start index
the index >= from
of the first element of this list buffer that satisfies the predicate p
,
or -1
, if none exists.
Finds index of first element satisfying some predicate.
Finds index of first element satisfying some predicate.
the predicate used to test elements.
the index of the first element of this list buffer that satisfies the predicate p
,
or -1
, if none exists.
Produces the range of all indices of this sequence.
Produces the range of all indices of this sequence.
a Range
value from 0
to one less than the length of this list buffer.
Selects all elements except the last.
Selects all elements except the last.
a list buffer consisting of all elements of this list buffer except the last one.
if the list buffer is empty.
Iterates over the inits of this list buffer.
Iterates over the inits of this list buffer. The first value will be this
list buffer and the final one will be an empty list buffer, with the intervening
values the results of successive applications of init
.
an iterator over all the inits of this list buffer
List(1,2,3).inits = Iterator(List(1,2,3), List(1,2), List(1), Nil)
Inserts new elements at a given index into this buffer.
Inserts new elements at a given index into this buffer.
the index where new elements are inserted.
the traversable collection containing the elements to insert.
if the index n
is not in the valid range
0 <= n <= length
.
Inserts new elements at the index n
.
Inserts new elements at the index n
. Opposed to method
update
, this method will not replace an element with a new
one. Instead, it will insert a new element at index n
.
the index where a new element will be inserted.
the iterable object providing all elements to insert.
if n
is out of bounds.
[use case] Computes the multiset intersection between this list buffer and another sequence.
Computes the multiset intersection between this list buffer and another sequence.
the sequence of elements to intersect with.
a new list buffer which contains all elements of this list buffer
which also appear in that
.
If an element value x
appears
n times in that
, then the first n occurrences of x
will be retained
in the result, but any following occurrences will be omitted.
Tests whether this list buffer contains given index.
Tests whether this list buffer contains given index.
The implementations of methods apply
and isDefinedAt
turn a Seq[A]
into
a PartialFunction[Int, A]
.
true
if this list buffer contains an element at position idx
, false
otherwise.
Tests whether this list buffer is empty.
Tests whether this list buffer is empty.
true
if the list buffer contain no elements, false
otherwise.
Test whether the dynamic type of the receiver object is T0
.
Test whether the dynamic type of the receiver object is T0
.
Note that the result of the test is modulo Scala's erasure semantics.
Therefore the expression 1.isInstanceOf[String]
will return false
, while the
expression List(1).isInstanceOf[List[String]]
will return true
.
In the latter example, because the type argument is erased as part of compilation it is
not possible to check whether the contents of the list are of the specified type.
true
if the receiver object is an instance of erasure of type T0
; false
otherwise.
Tests whether this list buffer can be repeatedly traversed.
Tests whether this list buffer can be repeatedly traversed.
true
Creates a new iterator over all elements contained in this iterable object.
Creates a new iterator over all elements contained in this iterable object.
the new iterator
Selects the last element.
Selects the last element.
The last element of this list buffer.
If the list buffer is empty.
[use case] Finds index of last occurrence of some value in this list buffer before or at a given end index.
Finds index of last occurrence of some value in this list buffer before or at a given end index.
the element value to search for.
the end index.
the index <= end
of the last element of this list buffer that is equal (as determined by ==
)
to elem
, or -1
, if none exists.
[use case] Finds index of last occurrence of some value in this list buffer.
Finds index of last occurrence of some value in this list buffer.
the element value to search for.
the index of the last element of this list buffer that is equal (as determined by ==
)
to elem
, or -1
, if none exists.
Finds last index before or at a given end index where this list buffer contains a given sequence as a slice.
Finds last index before or at a given end index where this list buffer contains a given sequence as a slice.
the sequence to test
the end index
the last index <= end
such that the elements of this list buffer starting at this index
match the elements of sequence that
, or -1
of no such subsequence exists.
Finds last index where this list buffer contains a given sequence as a slice.
Finds last index where this list buffer contains a given sequence as a slice.
the sequence to test
the last index such that the elements of this list buffer starting a this index
match the elements of sequence that
, or -1
of no such subsequence exists.
Finds index of last element satisfying some predicate before or at given end index.
Finds index of last element satisfying some predicate before or at given end index.
the predicate used to test elements.
the index <= end
of the last element of this list buffer that satisfies the predicate p
,
or -1
, if none exists.
Finds index of last element satisfying some predicate.
Finds index of last element satisfying some predicate.
the predicate used to test elements.
the index of the last element of this list buffer that satisfies the predicate p
,
or -1
, if none exists.
Optionally selects the last element.
Optionally selects the last element.
the last element of this list buffer$ if it is nonempty,
None
if it is empty.
The current length of the buffer.
The current length of the buffer.
This operation takes constant time.
the number of elements in this list buffer.
Compares the length of this list buffer to a test value.
Compares the length of this list buffer to a test value.
the test value that gets compared with the length.
A value x
where
x < 0 if this.length < len x == 0 if this.length == len x > 0 if this.length > len
The method as implemented here does not call length
directly; its running time
is O(length min len)
instead of O(length)
. The method should be overwritten
if computing length
is cheap.
Turns this partial function into a plain function returning an Option
result.
Turns this partial function into a plain function returning an Option
result.
a function that takes an argument x
to Some(this(x))
if this
is defined for x
, and to None
otherwise.
Function.unlift
[use case] Builds a new collection by applying a function to all elements of this list buffer.
Builds a new collection by applying a function to all elements of this list buffer.
the element type of the returned collection.
the function to apply to each element.
a new list buffer resulting from applying the given function
f
to each element of this list buffer and collecting the results.
Creates a new builder by applying a transformation function to the results of this builder.
Creates a new builder by applying a transformation function to the results of this builder.
the type of collection returned by f
.
the transformation function.
a new builder which is the same as the current builder except that a transformation function is applied to this builder's result.
[use case] Finds the largest element.
Finds the largest element.
the largest element of this list buffer.
[use case] Finds the smallest element.
Finds the smallest element.
the smallest element of this list buffer
Displays all elements of this list buffer in a string.
Displays all elements of this list buffer in a string.
a string representation of this list buffer. In the resulting string
the string representations (w.r.t. the method toString
)
of all elements of this list buffer follow each other without any
separator string.
Displays all elements of this list buffer in a string using a separator string.
Displays all elements of this list buffer in a string using a separator string.
the separator string.
a string representation of this list buffer. In the resulting string
the string representations (w.r.t. the method toString
)
of all elements of this list buffer are separated by the string sep
.
List(1, 2, 3).mkString("|") = "1|2|3"
Displays all elements of this list buffer in a string using start, end, and separator strings.
Displays all elements of this list buffer in a string using start, end, and separator strings.
the starting string.
the separator string.
the ending string.
a string representation of this list buffer. The resulting string
begins with the string start
and ends with the string
end
. Inside, the string representations (w.r.t. the method
toString
) of all elements of this list buffer are separated by
the string sep
.
List(1, 2, 3).mkString("(", "; ", ")") = "(1; 2; 3)"
Equivalent to !(this eq that)
.
Equivalent to !(this eq that)
.
true
if the argument is not a reference to the receiver object; false
otherwise.
The builder that builds instances of type ListBuffer
[A]
The builder that builds instances of type ListBuffer
[A]
Tests whether the list buffer is not empty.
Tests whether the list buffer is not empty.
true
if the list buffer contains at least one element, false
otherwise.
Wakes up a single thread that is waiting on the receiver object's monitor.
Wakes up a single thread that is waiting on the receiver object's monitor.
not specified by SLS as a member of AnyRef
Wakes up all threads that are waiting on the receiver object's monitor.
Wakes up all threads that are waiting on the receiver object's monitor.
not specified by SLS as a member of AnyRef
Composes this partial function with a fallback partial function which gets applied where this partial function is not defined.
Composes this partial function with a fallback partial function which gets applied where this partial function is not defined.
the argument type of the fallback function
the result type of the fallback function
the fallback function
a partial function which has as domain the union of the domains
of this partial function and that
. The resulting partial function
takes x
to this(x)
where this
is defined, and to that(x)
where it is not.
[use case] A copy of this list buffer with an element value appended until a given target length is reached.
A copy of this list buffer with an element value appended until a given target length is reached.
the target length
the padding value
a new list buffer consisting of
all elements of this list buffer followed by the minimal number of occurrences of elem
so
that the resulting list buffer has a length of at least len
.
Returns a parallel implementation of this collection.
Returns a parallel implementation of this collection.
For most collection types, this method creates a new parallel collection by copying
all the elements. For these collection, par
takes linear time. Mutable collections
in this category do not produce a mutable parallel collection that has the same
underlying dataset, so changes in one collection will not be reflected in the other one.
Specific collections (e.g. ParArray
or mutable.ParHashMap
) override this default
behaviour by creating a parallel collection which shares the same underlying dataset.
For these collections, par
takes constant or sublinear time.
All parallel collections return a reference to themselves.
a parallel implementation of this collection
The default par
implementation uses the combiner provided by this method
to create a new parallel collection.
The default par
implementation uses the combiner provided by this method
to create a new parallel collection.
a combiner for the parallel collection of type ParRepr
Partitions this list buffer in two list buffers according to a predicate.
Partitions this list buffer in two list buffers according to a predicate.
the predicate on which to partition.
a pair of list buffers: the first list buffer consists of all elements that
satisfy the predicate p
and the second list buffer consists of all elements
that don't. The relative order of the elements in the resulting list buffers
is the same as in the original list buffer.
[use case] Produces a new list buffer where a slice of elements in this list buffer is replaced by another sequence.
Produces a new list buffer where a slice of elements in this list buffer is replaced by another sequence.
the index of the first replaced element
the number of elements to drop in the original list buffer
a new list buffer consisting of all elements of this list buffer
except that replaced
elements starting from from
are replaced
by patch
.
Iterates over distinct permutations.
Iterates over distinct permutations.
An Iterator which traverses the distinct permutations of this list buffer.
"abb".permutations = Iterator(abb, bab, bba)
Returns the length of the longest prefix whose elements all satisfy some predicate.
Returns the length of the longest prefix whose elements all satisfy some predicate.
the predicate used to test elements.
the length of the longest prefix of this list buffer
such that every element of the segment satisfies the predicate p
.
Prepends given elements to this buffer.
Prepends the elements contained in a traversable object to this buffer.
Prepends the elements contained in a traversable object to this buffer.
the collection containing the elements to prepend.
Prepends the elements of this buffer to a given list
Prepends the elements of this buffer to a given list
the list to which elements are prepended
[use case] Multiplies up the elements of this collection.
Multiplies up the elements of this collection.
the product of all elements in this list buffer of numbers of type Int
.
Instead of Int
, any other type T
with an implicit Numeric[T]
implementation
can be used as element type of the list buffer and as result type of product
.
Examples of such types are: Long
, Float
, Double
, BigInt
.
expose the underlying list but do not mark it as exported
expose the underlying list but do not mark it as exported
A sequence which refers to this buffer for all its operations.
Reduces the elements of this list buffer using the specified associative binary operator.
Reduces the elements of this list buffer using the specified associative binary operator.
The order in which operations are performed on elements is unspecified and may be nondeterministic.
A type parameter for the binary operator, a supertype of A
.
A binary operator that must be associative.
The result of applying reduce operator op
between all the elements if the list buffer is nonempty.
if this list buffer is empty.
Applies a binary operator to all elements of this list buffer, going left to right.
Applies a binary operator to all elements of this list buffer, going left to right.
the result type of the binary operator.
the binary operator.
the result of inserting op
between consecutive elements of this list buffer,
going left to right:
op( op( ... op(x_1, x_2) ..., x_{n-1}), x_n)
where x1, ..., xn
are the elements of this list buffer.
if this list buffer is empty.
Optionally applies a binary operator to all elements of this list buffer, going left to right.
Optionally applies a binary operator to all elements of this list buffer, going left to right.
the result type of the binary operator.
the binary operator.
an option value containing the result of reduceLeft(op)
is this list buffer is nonempty,
None
otherwise.
Reduces the elements of this list buffer, if any, using the specified associative binary operator.
Reduces the elements of this list buffer, if any, using the specified associative binary operator.
The order in which operations are performed on elements is unspecified and may be nondeterministic.
A type parameter for the binary operator, a supertype of A
.
A binary operator that must be associative.
An option value containing result of applying reduce operator op
between all
the elements if the collection is nonempty, and None
otherwise.
Applies a binary operator to all elements of this list buffer, going right to left.
Applies a binary operator to all elements of this list buffer, going right to left.
the result type of the binary operator.
the binary operator.
the result of inserting op
between consecutive elements of this list buffer,
going right to left:
op(x_1, op(x_2, ..., op(x_{n-1}, x_n)...))
where x1, ..., xn
are the elements of this list buffer.
if this list buffer is empty.
Optionally applies a binary operator to all elements of this list buffer, going right to left.
Optionally applies a binary operator to all elements of this list buffer, going right to left.
the result type of the binary operator.
the binary operator.
an option value containing the result of reduceRight(op)
is this list buffer is nonempty,
None
otherwise.
Removes the element on a given index position.
Removes the element on a given index position. May take time linear in the buffer size.
the index which refers to the element to delete.
n the element that was formerly at position n
.
if n
is out of bounds.
an element must exists at position n
.
Removes a given number of elements on a given index position.
Removes a given number of elements on a given index position. May take time linear in the buffer size.
the index which refers to the first element to remove.
the number of elements to remove.
(Changed in version 2.11) Invalid input values will be rejected in future releases.
The collection of type list buffer underlying this TraversableLike
object.
The collection of type list buffer underlying this TraversableLike
object.
By default this is implemented as the TraversableLike
object itself,
but this can be overridden.
Produces a collection from the added elements.
Produces a collection from the added elements. The builder's contents are undefined after this operation.
a collection containing the elements added to this builder.
Returns new list buffer wih elements in reversed order.
Returns new list buffer wih elements in reversed order.
A new list buffer with all elements of this list buffer in reversed order.
An iterator yielding elements in reversed order.
An iterator yielding elements in reversed order.
Note: xs.reverseIterator
is the same as xs.reverse.iterator
but might be more efficient.
an iterator yielding the elements of this list buffer in reversed order
[use case] Builds a new collection by applying a function to all elements of this list buffer and collecting the results in reversed order.
Builds a new collection by applying a function to all elements of this list buffer and collecting the results in reversed order.
Note: xs.reverseMap(f)
is the same as xs.reverse.map(f)
but might be more efficient.
the element type of the returned collection.
the function to apply to each element.
a new list buffer resulting from applying the given function
f
to each element of this list buffer and collecting the results in reversed order.
Composes this partial function with an action function which gets applied to results of this partial function.
Composes this partial function with an action function which gets applied to results of this partial function. The action function is invoked only for its side effects; its result is ignored.
Note that expression pf.runWith(action)(x)
is equivalent to
if(pf isDefinedAt x) { action(pf(x)); true } else false
except that runWith
is implemented via applyOrElse
and thus potentially more efficient.
Using runWith
avoids double evaluation of pattern matchers and guards for partial function literals.
the action function
a function which maps arguments x
to isDefinedAt(x)
. The resulting function
runs action(this(x))
where this
is defined.
2.10
applyOrElse
.
[use case] Checks if the other iterable collection contains the same elements in the same order as this list buffer.
Checks if the other iterable collection contains the same elements in the same order as this list buffer.
the collection to compare with.
true
, if both collections contain the same elements in the same order, false
otherwise.
Computes a prefix scan of the elements of the collection.
Computes a prefix scan of the elements of the collection.
Note: The neutral element z
may be applied more than once.
element type of the resulting collection
type of the resulting collection
neutral element for the operator op
the associative operator for the scan
combiner factory which provides a combiner
a new list buffer containing the prefix scan of the elements in this list buffer
Produces a collection containing cumulative results of applying the operator going left to right.
Produces a collection containing cumulative results of applying the operator going left to right.
the type of the elements in the resulting collection
the actual type of the resulting collection
the initial value
the binary operator applied to the intermediate result and the element
an implicit value of class CanBuildFrom
which determines the
result class That
from the current representation type Repr
and the new element type B
. This is usually the canBuildFrom
value
defined in object ListBuffer
.
collection with intermediate results
Produces a collection containing cumulative results of applying the operator going right to left.
Produces a collection containing cumulative results of applying the operator going right to left. The head of the collection is the last cumulative result.
Example:
List(1, 2, 3, 4).scanRight(0)(_ + _) == List(10, 9, 7, 4, 0)
the type of the elements in the resulting collection
the actual type of the resulting collection
the initial value
the binary operator applied to the intermediate result and the element
an implicit value of class CanBuildFrom
which determines the
result class That
from the current representation type Repr
and the new element type B
. This is usually the canBuildFrom
value
defined in object ListBuffer
.
collection with intermediate results
(Changed in version 2.9.0) The behavior of scanRight
has changed. The previous behavior can be reproduced with scanRight.reverse.
Computes length of longest segment whose elements all satisfy some predicate.
Computes length of longest segment whose elements all satisfy some predicate.
the predicate used to test elements.
the index where the search starts.
the length of the longest segment of this list buffer starting from index from
such that every element of the segment satisfies the predicate p
.
A version of this collection with all of the operations implemented sequentially (i.
A version of this collection with all of the operations implemented sequentially (i.e. in a single-threaded manner).
This method returns a reference to this collection. In parallel collections, it is redefined to return a sequential implementation of this collection. In both cases, it has O(1) complexity.
a sequential view of the collection.
The size of this list buffer.
The size of this list buffer.
the number of elements in this list buffer.
Gives a hint that one expects the result
of this builder
to have the same size as the given collection, plus some delta.
Gives a hint that one expects the result
of this builder
to have the same size as the given collection, plus some delta. This will
provide a hint only if the collection is known to have a cheap
size
method. Currently this is assumed to be the case if and only if
the collection is of type IndexedSeqLike
.
Some builder classes
will optimize their representation based on the hint. However,
builder implementations are still required to work correctly even if the hint is
wrong, i.e. a different number of elements is added.
the collection which serves as a hint for the result's size.
a correction to add to the coll.size
to produce the size hint.
Gives a hint that one expects the result
of this builder
to have the same size as the given collection, plus some delta.
Gives a hint that one expects the result
of this builder
to have the same size as the given collection, plus some delta. This will
provide a hint only if the collection is known to have a cheap
size
method. Currently this is assumed to be the case if and only if
the collection is of type IndexedSeqLike
.
Some builder classes
will optimize their representation based on the hint. However,
builder implementations are still required to work correctly even if the hint is
wrong, i.e. a different number of elements is added.
the collection which serves as a hint for the result's size.
Gives a hint how many elements are expected to be added
when the next result
is called.
Gives a hint how many elements are expected to be added
when the next result
is called. Some builder classes
will optimize their representation based on the hint. However,
builder implementations are still required to work correctly even if the hint is
wrong, i.e. a different number of elements is added.
the hint how many elements will be added.
Gives a hint how many elements are expected to be added
when the next result
is called, together with an upper bound
given by the size of some other collection.
Gives a hint how many elements are expected to be added
when the next result
is called, together with an upper bound
given by the size of some other collection. Some builder classes
will optimize their representation based on the hint. However,
builder implementations are still required to work correctly even if the hint is
wrong, i.e. a different number of elements is added.
the hint how many elements will be added.
the bounding collection. If it is an IndexedSeqLike, then sizes larger than collection's size are reduced.
Selects an interval of elements.
Selects an interval of elements. The returned collection is made up
of all elements x
which satisfy the invariant:
from <= indexOf(x) < until
a list buffer containing the elements greater than or equal to
index from
extending up to (but not including) index until
of this list buffer.
Groups elements in fixed size blocks by passing a "sliding window" over them (as opposed to partitioning them, as is done in grouped.
Groups elements in fixed size blocks by passing a "sliding window" over them (as opposed to partitioning them, as is done in grouped.)
the number of elements per group
the distance between the first elements of successive groups (defaults to 1)
An iterator producing list buffers of size size
, except the
last and the only element will be truncated if there are
fewer elements than size.
scala.collection.Iterator, method sliding
Groups elements in fixed size blocks by passing a "sliding window" over them (as opposed to partitioning them, as is done in grouped.
Groups elements in fixed size blocks by passing a "sliding window" over them (as opposed to partitioning them, as is done in grouped.)
the number of elements per group
An iterator producing list buffers of size size
, except the
last and the only element will be truncated if there are
fewer elements than size.
scala.collection.Iterator, method sliding
Sorts this ListBuffer
according to the Ordering which results from transforming
an implicitly given Ordering with a transformation function.
Sorts this ListBuffer
according to the Ordering which results from transforming
an implicitly given Ordering with a transformation function.
the target type of the transformation f
, and the type where
the ordering ord
is defined.
the transformation function mapping elements
to some other domain B
.
the ordering assumed on domain B
.
a list buffer consisting of the elements of this list buffer
sorted according to the ordering where x < y
if
ord.lt(f(x), f(y))
.
val words = "The quick brown fox jumped over the lazy dog".split(' ') // this works because scala.Ordering will implicitly provide an Ordering[Tuple2[Int, Char]] words.sortBy(x => (x.length, x.head)) res0: Array[String] = Array(The, dog, fox, the, lazy, over, brown, quick, jumped)
Sorts this list buffer according to a comparison function.
Sorts this list buffer according to a comparison function.
The sort is stable. That is, elements that are equal (as determined by
lt
) appear in the same order in the sorted sequence as in the original.
the comparison function which tests whether its first argument precedes its second argument in the desired ordering.
a list buffer consisting of the elements of this list buffer
sorted according to the comparison function lt
.
List("Steve", "Tom", "John", "Bob").sortWith(_.compareTo(_) < 0) = List("Bob", "John", "Steve", "Tom")
Sorts this list buffer according to an Ordering.
Sorts this list buffer according to an Ordering.
The sort is stable. That is, elements that are equal (as determined by
lt
) appear in the same order in the sorted sequence as in the original.
the ordering to be used to compare elements.
a list buffer consisting of the elements of this list buffer
sorted according to the ordering ord
.
Splits this list buffer into a prefix/suffix pair according to a predicate.
Splits this list buffer into a prefix/suffix pair according to a predicate.
Note: c span p
is equivalent to (but possibly more efficient than)
(c takeWhile p, c dropWhile p)
, provided the evaluation of the
predicate p
does not cause any side-effects.
a pair consisting of the longest prefix of this list buffer whose
elements all satisfy p
, and the rest of this list buffer.
Splits this list buffer into two at a given position.
Splits this list buffer into two at a given position.
Note: c splitAt n
is equivalent to (but possibly more efficient than)
(c take n, c drop n)
.
the position at which to split.
a pair of list buffers consisting of the first n
elements of this list buffer, and the other elements.
Tests whether this list buffer starts with the given sequence.
Tests whether this list buffer starts with the given sequence.
the sequence to test
true
if this collection has that
as a prefix, false
otherwise.
Tests whether this list buffer contains the given sequence at a given index.
Tests whether this list buffer contains the given sequence at a given index.
Note: If the both the receiver object this
and the argument
that
are infinite sequences this method may not terminate.
the sequence to test
the index where the sequence is searched.
true
if the sequence that
is contained in this list buffer at
index offset
, otherwise false
.
Defines the prefix of the string representation.
Defines the prefix of the string representation.
the string representation of this buffer.
[use case] Sums up the elements of this collection.
Sums up the elements of this collection.
the sum of all elements in this list buffer of numbers of type Int
.
Instead of Int
, any other type T
with an implicit Numeric[T]
implementation
can be used as element type of the list buffer and as result type of sum
.
Examples of such types are: Long
, Float
, Double
, BigInt
.
Selects all elements except the first.
Selects all elements except the first.
a list buffer consisting of all elements of this list buffer except the first one.
if the list buffer is empty.
Iterates over the tails of this list buffer.
Iterates over the tails of this list buffer. The first value will be this
list buffer and the final one will be an empty list buffer, with the intervening
values the results of successive applications of tail
.
an iterator over all the tails of this list buffer
List(1,2,3).tails = Iterator(List(1,2,3), List(2,3), List(3), Nil)
Selects first n elements.
Selects first n elements.
the number of elements to take from this list buffer.
a list buffer consisting only of the first n
elements of this list buffer,
or else the whole list buffer, if it has less than n
elements.
Selects last n elements.
Selects last n elements.
the number of elements to take
a list buffer consisting only of the last n
elements of this list buffer, or else the
whole list buffer, if it has less than n
elements.
Takes longest prefix of elements that satisfy a predicate.
Takes longest prefix of elements that satisfy a predicate.
the longest prefix of this list buffer whose elements all satisfy
the predicate p
.
The underlying collection seen as an instance of
.ListBuffer
The underlying collection seen as an instance of
.
By default this is implemented as the current collection object itself,
but this can be overridden.
ListBuffer
[use case] Converts this list buffer into another by copying all elements.
Converts this list buffer into another by copying all elements.
The collection type to build.
a new collection containing all elements of this list buffer.
[use case] Converts this list buffer to an array.
Converts this list buffer to an array.
an array containing all elements of this list buffer.
An ClassTag
must be available for the element type of this list buffer.
Converts this list buffer to a mutable buffer.
Converts this list buffer to a mutable buffer.
a buffer containing all elements of this list buffer.
A conversion from collections of type Repr
to
objects.ListBuffer
A conversion from collections of type Repr
to
objects.
By default this is implemented as just a cast, but this can be overridden.
ListBuffer
Converts this list buffer to an indexed sequence.
Converts this list buffer to an indexed sequence.
an indexed sequence containing all elements of this list buffer.
Converts this list buffer to an iterable collection.
Converts this list buffer to an iterable collection. Note that
the choice of target Iterable
is lazy in this default implementation
as this TraversableOnce
may be lazy and unevaluated (i.e. it may
be an iterator which is only traversable once).
an Iterable
containing all elements of this list buffer.
Returns an Iterator over the elements in this list buffer.
Returns an Iterator over the elements in this list buffer. Will return the same Iterator if this instance is already an Iterator.
an Iterator containing all elements of this list buffer.
Converts this buffer to a list.
Converts this buffer to a list. Takes constant time. The buffer is copied lazily, the first time it is mutated.
a list containing all elements of this list buffer.
[use case] Converts this list buffer to a map.
Converts this list buffer to a map. This method is unavailable unless the elements are members of Tuple2, each ((T, U)) becoming a key-value pair in the map. Duplicate keys will be overwritten by later keys: if this is an unordered collection, which key is in the resulting map is undefined.
a map of type immutable.Map[T, U]
containing all key/value pairs of type (T, U)
of this list buffer.
Converts this list buffer to a sequence.
Converts this list buffer to a sequence. As with toIterable
, it's lazy
in this default implementation, as this TraversableOnce
may be
lazy and unevaluated.
a sequence containing all elements of this list buffer.
Converts this list buffer to a set.
Converts this list buffer to a set.
a set containing all elements of this list buffer.
Converts this list buffer to a stream.
Converts this list buffer to a stream.
a stream containing all elements of this list buffer.
Converts this list buffer to a string.
Converts this list buffer to a string.
a string representation of this collection. By default this
string consists of the stringPrefix
of this list buffer, followed
by all elements separated by commas and enclosed in parentheses.
Converts this list buffer to an unspecified Traversable.
Converts this list buffer to an unspecified Traversable. Will return the same collection if this instance is already Traversable.
a Traversable containing all elements of this list buffer.
Converts this list buffer to a Vector.
Converts this list buffer to a Vector.
a vector containing all elements of this list buffer.
Applies a transformation function to all values contained in this sequence.
Applies a transformation function to all values contained in this sequence. The transformation function produces new values from existing elements.
the transformation to apply
the sequence itself.
Transposes this list buffer of traversable collections into a list buffer of list buffers.
Transposes this list buffer of traversable collections into a list buffer of list buffers.
the type of the elements of each traversable collection.
an implicit conversion which asserts that the
element type of this list buffer is a Traversable
.
a two-dimensional list buffer of list buffers which has as nth row the nth column of this list buffer.
(Changed in version 2.9.0) transpose
throws an IllegalArgumentException
if collections are not uniformly sized.
if all collections in this list buffer are not of the same size.
Removes the last n elements of this buffer.
Removes the last n elements of this buffer.
the number of elements to remove from the end of this buffer.
Removes the first n elements of this buffer.
Removes the first n elements of this buffer.
the number of elements to remove from the beginning of this buffer.
The iterable object to which calls are forwarded
The iterable object to which calls are forwarded
[use case] Produces a new sequence which contains all elements of this list buffer and also all elements of a given sequence.
Produces a new sequence which contains all elements of this list buffer and also all elements of
a given sequence. xs union ys
is equivalent to xs ++ ys
.
Another way to express this
is that xs union ys
computes the order-presevring multi-set union of xs
and ys
.
union
is hence a counter-part of diff
and intersect
which also work on multi-sets.
the sequence to add.
a new list buffer which contains all elements of this list buffer
followed by all elements of that
.
Converts this list buffer of pairs into two collections of the first and second half of each pair.
Converts this list buffer of pairs into two collections of the first and second half of each pair.
the type of the first half of the element pairs
the type of the second half of the element pairs
an implicit conversion which asserts that the element type of this list buffer is a pair.
a pair list buffers, containing the first, respectively second half of each element pair of this list buffer.
Converts this list buffer of triples into three collections of the first, second, and third element of each triple.
Converts this list buffer of triples into three collections of the first, second, and third element of each triple.
the type of the first member of the element triples
the type of the second member of the element triples
the type of the third member of the element triples
an implicit conversion which asserts that the element type of this list buffer is a triple.
a triple list buffers, containing the first, second, respectively third member of each element triple of this list buffer.
Replaces element at index n
with the new element
newelem
.
Replaces element at index n
with the new element
newelem
. Takes time linear in the buffer size. (except the
first element, which is updated in constant time).
the index of the element to replace.
the new element.
if n
is out of bounds.
[use case] A copy of this list buffer with one single replaced element.
A copy of this list buffer with one single replaced element.
the position of the replacement
the replacing element
a copy of this list buffer with the element at position index
replaced by elem
.
Creates a non-strict view of a slice of this list buffer.
Creates a non-strict view of a slice of this list buffer.
Note: the difference between view
and slice
is that view
produces
a view of the current list buffer, whereas slice
produces a new list buffer.
Note: view(from, to)
is equivalent to view.slice(from, to)
the index of the first element of the view
the index of the element following the view
a non-strict view of a slice of this list buffer, starting at index from
and extending up to (but not including) index until
.
Creates a non-strict view of this list buffer.
Creates a non-strict view of this list buffer.
a non-strict view of this list buffer.
Creates a non-strict filter of this list buffer.
Creates a non-strict filter of this list buffer.
Note: the difference between c filter p
and c withFilter p
is that
the former creates a new collection, whereas the latter only
restricts the domain of subsequent map
, flatMap
, foreach
,
and withFilter
operations.
the predicate used to test elements.
an object of class WithFilter
, which supports
map
, flatMap
, foreach
, and withFilter
operations.
All these operations apply to those elements of this list buffer
which satisfy the predicate p
.
[use case] Returns a list buffer formed from this list buffer and another iterable collection by combining corresponding elements in pairs.
Returns a list buffer formed from this list buffer and another iterable collection by combining corresponding elements in pairs. If one of the two collections is longer than the other, its remaining elements are ignored.
the type of the second half of the returned pairs
The iterable providing the second half of each result pair
a new list buffer containing pairs consisting of
corresponding elements of this list buffer and that
. The length
of the returned collection is the minimum of the lengths of this list buffer and that
.
[use case] Returns a list buffer formed from this list buffer and another iterable collection by combining corresponding elements in pairs.
Returns a list buffer formed from this list buffer and another iterable collection by combining corresponding elements in pairs. If one of the two collections is shorter than the other, placeholder elements are used to extend the shorter collection to the length of the longer.
the type of the second half of the returned pairs
The iterable providing the second half of each result pair
the element to be used to fill up the result if this list buffer is shorter than that
.
the element to be used to fill up the result if that
is shorter than this list buffer.
a new list buffer containing pairs consisting of
corresponding elements of this list buffer and that
. The length
of the returned collection is the maximum of the lengths of this list buffer and that
.
If this list buffer is shorter than that
, thisElem
values are used to pad the result.
If that
is shorter than this list buffer, thatElem
values are used to pad the result.
[use case] Zips this list buffer with its indices.
Zips this list buffer with its indices.
A new list buffer containing pairs consisting of all elements of this
list buffer paired with their index. Indices start at 0
.
List("a", "b", "c").zipWithIndex = List(("a", 0), ("b", 1), ("c", 2))
(listBuffer: MonadOps[A]).filter(p)
(listBuffer: MonadOps[A]).flatMap(f)
(listBuffer: MonadOps[A]).map(f)
(listBuffer: StringAdd).self
(listBuffer: StringFormat).self
(listBuffer: MonadOps[A]).withFilter(p)
A syntactic sugar for out of order folding.
A syntactic sugar for out of order folding. See fold
.
Example:
scala> val a = LinkedList(1,2,3,4) a: scala.collection.mutable.LinkedList[Int] = LinkedList(1, 2, 3, 4) scala> val b = (a /:\ 5)(_+_) b: Int = 15
(Since version 2.10.0) use fold instead
(listBuffer: ArrowAssoc[ListBuffer[A]]).x
(Since version 2.10.0) Use leftOfArrow
instead
(listBuffer: Ensuring[ListBuffer[A]]).x
(Since version 2.10.0) Use resultOfEnsuring
instead
A
Buffer
implementation back up by a list. It provides constant time prepend and append. Most other operations are linear.the type of this list buffer's elements.
2.8
1
"Scala's Collection Library overview" section on
List Buffers
for more information.