Scala Library: scala.collection.mutable.LazyBuilder
scala.collection.mutable.LazyBuilder
A builder that constructs its result lazily. Iterators or iterables to be added
to this builder with ++=
are not evaluated until result
is called.
This builder can be reused.
- Elem
- type of the elements for this builder.
- To
- type of the collection this builder builds.
- Source
- Since
- 2.8
Concrete Value Members From scala.collection.generic.Growable
def +=(elem1: Elem, elem2: Elem, elems: Elem*): LazyBuilder.this.type
adds two or more elements to this growable collection.
- elem1
- the first element to add.
- elem2
- the second element to add.
- elems
- the remaining elements to add.
- returns
- the growable collection itself
- Definition Classes
- Growable
(defined at scala.collection.generic.Growable)
Concrete Value Members From scala.collection.mutable.Builder
def mapResult[NewTo](f: (To) ⇒ NewTo): Builder[Elem, NewTo]
Creates a new builder by applying a transformation function to the results of this builder.
- NewTo
- the type of collection returned by
f
.
- the type of collection returned by
- f
- the transformation function.
- returns
- a new builder which is the same as the current builder except that a transformation function is applied to this builder’s result.
- Definition Classes
- Builder
- Note
- The original builder should no longer be used after
mapResult
is called.
- The original builder should no longer be used after
(defined at scala.collection.mutable.Builder)
def sizeHint(size: Int): Unit
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.
- size
- the hint how many elements will be added.
- Definition Classes
- Builder
(defined at scala.collection.mutable.Builder)
def sizeHint(coll: TraversableLike[_, _]): Unit
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.
- coll
- the collection which serves as a hint for the result’s size.
- Definition Classes
- Builder
(defined at scala.collection.mutable.Builder)
def sizeHint(coll: TraversableLike[_, _], delta: Int): Unit
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.
- coll
- the collection which serves as a hint for the result’s size.
- delta
- a correction to add to the
coll.size
to produce the size hint.
- a correction to add to the
- Definition Classes
- Builder
(defined at scala.collection.mutable.Builder)
def sizeHintBounded(size: Int, boundingColl: TraversableLike[_, _]): Unit
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.
- size
- the hint how many elements will be added.
- boundingColl
- the bounding collection. If it is an IndexedSeqLike, then sizes larger than collection’s size are reduced.
- Definition Classes
- Builder
(defined at scala.collection.mutable.Builder)
Concrete Value Members From scala.collection.mutable.LazyBuilder
abstract def result(): To
Produces a collection from the added elements.
After a call to result
, the behavior of all other methods is undefined save
for clear
. If clear
is called, then the builder is reset and may be used to
build another instance.
- returns
- a collection containing the elements added to this builder.
- Definition Classes
- LazyBuilder → ReusableBuilder → Builder
(defined at scala.collection.mutable.LazyBuilder)
def ++=(xs: TraversableOnce[Elem]): LazyBuilder.this.type
adds all elements produced by a TraversableOnce to this growable collection.
- xs
- the TraversableOnce producing the elements to add.
- returns
- the growable collection itself.
- Definition Classes
- LazyBuilder → Growable
(defined at scala.collection.mutable.LazyBuilder)
def +=(x: Elem): LazyBuilder.this.type
Adds a single element to the builder.
- returns
- the builder itself.
- Definition Classes
- LazyBuilder → Builder → Growable
(defined at scala.collection.mutable.LazyBuilder)
var parts: ListBuffer[TraversableOnce[Elem]]
The different segments of elements to be added to the builder, represented as iterators
- Attributes
- protected
(defined at scala.collection.mutable.LazyBuilder)
Instance Constructors From scala.collection.mutable.LazyBuilder
new LazyBuilder()
(defined at scala.collection.mutable.LazyBuilder)
Full Source:
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