scala.collection.immutable.Stream
The type implementing this traversable
A lazier implementation of WithFilter than TraversableLike's.
A class supporting filtered operations.
o != arg0 is the same as !(o == (arg0)).
o != arg0 is the same as !(o == (arg0)).
the object to compare against this object for dis-equality.
false if the receiver object is equivalent to the argument; true otherwise.
Create a new stream which contains all elements of this stream
followed by all elements of Traversable that.
Create a new stream which contains all elements of this stream
followed by all elements of Traversable that.
the element type of the returned collection.
the class of the returned collection. Where possible, That is
the same class as the current collection class Repr, but this
depends on the element type B being admissible for that class,
which means that an implicit instance of type CanBuildFrom[Repr, B, That] is found.
an implicit value of class CanBuildFrom which determines the
result class That from the current representation type Repr and the new element type B.
a new collection of type That which contains all elements of this stream
followed by all elements of that.
[use case] Prepends an element to this stream
Prepends an element to this stream
the prepended element
a new stream consisting of elem followed
by all elements of this stream.
Prepends an element to this stream
Prepends an element to this stream
the element type of the returned stream.
the class of the returned collection. Where possible, That is
the same class as the current collection class Repr, but this
depends on the element type B being admissible for that class,
which means that an implicit instance of type CanBuildFrom[Repr, B, That] is found.
the prepended 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.
a new collection of type That consisting of elem followed
by all elements of this stream.
Applies a binary operator to a start value and all elements of this stream, going left to right.
Applies a binary operator to a start value and all elements of this stream, going left to right.
Note: /: is alternate syntax for foldLeft; z /: xs is the same as xs foldLeft z.
Note: will not terminate for infinite-sized collections.
the result type of the binary operator.
the start value.
the binary operator.
the result of inserting op between consecutive elements of this stream,
going left to right with the start value z on the left:
op(...op(op(z, x1), x2), ..., xn)
where x,,1,,, ..., x,,n,, are the elements of this stream.
[use case] Appends an element to this stream
Appends an element to this stream
Note: will not terminate for infinite-sized collections.
the appended element
a new stream consisting of
all elements of this stream followed by elem.
Appends an element to this stream
Appends an element to this stream
Note: will not terminate for infinite-sized collections.
the element type of the returned stream.
the class of the returned collection. Where possible, That is
the same class as the current collection class Repr, but this
depends on the element type B being admissible for that class,
which means that an implicit instance of type CanBuildFrom[Repr, B, That] is found.
the appended 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.
a new collection of type That consisting of
all elements of this stream followed by elem.
Applies a binary operator to all elements of this stream and a start value, going right to left.
Applies a binary operator to all elements of this stream and a start value, going right to left.
Note: :\ is alternate syntax for foldRight; xs :\ z is the same as xs foldRight z.
Note: will not terminate for infinite-sized collections.
the result type of the binary operator.
the start value
the binary operator
the result of inserting op between consecutive elements of this stream,
going right to left with the start value z on the right:
op(x1, op(x2, ... op(xn, z)...))
where x,,1,,, ..., x,,n,, are the elements of this stream.
o == arg0 is the same as if (o eq null) arg0 eq null else o.equals(arg0).
o == arg0 is the same as if (o eq null) arg0 eq null else o.equals(arg0).
the object to compare against this object for equality.
true if the receiver object is equivalent to the argument; false otherwise.
o == arg0 is the same as o.equals(arg0).
o == arg0 is the same as o.equals(arg0).
the object to compare against this object for equality.
true if the receiver object is equivalent to the argument; false otherwise.
Write all defined elements of this iterable into given string builder.
Write all defined elements of this iterable into given string builder.
The written text begins with the string start and is finished by the string
end. Inside, the string representations of defined elements (w.r.t.
the method toString()) are separated by the string
sep. The method will not force evaluation of undefined elements. A
tail of such elements will be represented by a "?" instead.@param b 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.
Appends all elements of this stream to a string builder.
Appends all elements of this stream to a string builder.
The written text consists of the string representations (w.r.t. the method toString)
of all elements of this stream without any separator string.
the string builder to which elements are appended.
the string builder b to which elements were appended.
Appends all elements of this stream to a string builder using a separator string.
Appends all elements of this stream 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 stream, separated by the string sep.
the string builder to which elements are appended.
the separator string.
the string builder b to which elements were appended.
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)).
The stream resulting from the concatenation of this stream with the argument stream.
The stream resulting from the concatenation of this stream with the argument stream.
The stream that gets appended to this stream
The stream containing elements of this stream and the traversable object.
Selects an element by its index in the stream.
Selects an element by its index in the stream.
Note: the execution of apply may take time proportial to the index value.
This method is used to cast the receiver object to be of type T0.
This method is used to 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 expression1.asInstanceOf[String] will throw a ClassCastException at runtime, while the expressionList(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 typed.
the receiver object.
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 stream should be compared
true, if this stream can possibly equal that, false otherwise. The test
takes into consideration only the run-time types of objects but ignores their elements.
This method creates and returns a copy of the receiver object.
This method creates and returns a copy of the receiver object.
The default implementation of the clone method is platform dependent.
a copy of the receiver object.
[use case] Builds a new collection by applying a partial function to all elements of this stream on which the function is defined.
Builds a new collection by applying a partial function to all elements of this stream on which the function is defined.
the element type of the returned collection.
the partial function which filters and maps the stream.
a new stream 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.
Builds a new collection by applying a partial function to all elements of this stream on which the function is defined.
Builds a new collection by applying a partial function to all elements of this stream on which the function is defined.
the element type of the returned collection.
the class of the returned collection. Where possible, That is
the same class as the current collection class Repr, but this
depends on the element type B being admissible for that class,
which means that an implicit instance of type CanBuildFrom[Repr, B, That] is found.
the partial function which filters and maps the stream.
an implicit value of class CanBuildFrom which determines the
result class That from the current representation type Repr and the new element type B.
a new collection of type That resulting from applying the partial function
pf to each element on which it is defined and collecting the results.
The order of the elements is preserved.
The factory companion object that builds instances of class Stream.
The factory companion object that builds instances of class Stream.
(f compose g)(x) == f(g(x))
(f compose g)(x) == f(g(x))
Tests whether this stream contains a given value as an element.
Tests whether this stream contains a given value as an element.
Note: may not terminate for infinite-sized collections.
the element to test.
true if this stream has an element that is
is equal (wrt ==) to elem, false otherwise.
Tests whether this stream contains a given sequence as a slice.
Tests whether this stream contains a given sequence as a slice.
Note: may not terminate for infinite-sized collections.
the sequence to test
true if this stream contains a slice with the same elements
as that, otherwise false.
[use case] Copies elements of this stream to an array.
Copies elements of this stream to an array.
Fills the given array xs with at most len elements of
this stream, starting at position start.
Copying will stop once either the end of the current stream 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 elements of this stream to an array.
Copies elements of this stream to an array.
Fills the given array xs with at most len elements of
this stream, starting at position start.
Copying will stop once either the end of the current stream is reached,
or the end of the array is reached, or len elements have been copied.
Note: will not terminate for infinite-sized collections.
the type of the elements of the array.
the array to fill.
the starting index.
the maximal number of elements to copy.
[use case] Copies values of this stream to an array.
Copies values of this stream to an array.
Fills the given array xs with values of this stream.
Copying will stop once either the end of the current stream is reached,
or the end of the array is reached.
the array to fill.
Copies values of this stream to an array.
Copies values of this stream to an array.
Fills the given array xs with values of this stream.
Copying will stop once either the end of the current stream is reached,
or the end of the array is reached.
Note: will not terminate for infinite-sized collections.
the type of the elements of the array.
the array to fill.
[use case] Copies values of this stream to an array.
Copies values of this stream to an array.
Fills the given array xs with values of this stream, after skipping start values.
Copying will stop once either the end of the current stream is reached,
or the end of the array is reached.
the array to fill.
the starting index.
Copies values of this stream to an array.
Copies values of this stream to an array.
Fills the given array xs with values of this stream, after skipping start values.
Copying will stop once either the end of the current stream is reached,
or the end of the array is reached.
Note: will not terminate for infinite-sized collections.
the type of the elements of the array.
the array to fill.
the starting index.
Copies all elements of this stream to a buffer.
Copies all elements of this stream to a buffer.
Note: will not terminate for infinite-sized collections.
The buffer to which elements are copied.
Tests whether every element of this stream relates to the corresponding element of another sequence by satisfying a test predicate.
Tests whether every element of this stream 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 stream
and y of that, otherwise false.
Counts the number of elements in the stream which satisfy a predicate.
Counts the number of elements in the stream 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 stream and another sequence.
Computes the multiset difference between this stream and another sequence.
Note: will not terminate for infinite-sized collections.
the sequence of elements to remove
a new stream which contains all elements of this stream
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.
Computes the multiset difference between this stream and another sequence.
Computes the multiset difference between this stream and another sequence.
Note: will not terminate for infinite-sized collections.
the element type of the returned stream.
the sequence of elements to remove
a new collection of type That which contains all elements of this stream
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 stream from this stream in which any duplicates (wrt to ==) removed.
Selects all elements except first n ones.
Selects all elements except first n ones.
the number of elements to drop from this stream.
a stream consisting of all elements of this stream except the first n ones, or else the
empty stream, if this stream 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 stream consisting of all elements of this stream except the first n ones, or else the
empty stream, if this stream has less than n elements.
Returns the longest suffix of this iterable whose first element
does not satisfy the predicate p.
Returns the longest suffix of this iterable whose first element
does not satisfy the predicate p.
the test predicate.@return the longest suffix of this stream whose first element
does not satisfy the predicate p.
use iterator' instead
Tests whether this stream ends with the given sequence.
Tests whether this stream ends with the given sequence.
Note: will not terminate for infinite-sized collections.
the sequence to test
true if this stream has that as a suffix, false otherwise.
This method is used to test whether the argument (arg0) is a reference to the
receiver object (this).
This method is used to test whether the argument (arg0) is a reference to the
receiver object (this).
The eq method implements an [http://en.wikipedia.org/wiki/Equivalence_relation equivalence relation] on
non-null instances of AnyRef:
* It is reflexive: for any non-null instance x of type AnyRef, x.eq(x) returns true.
* It is symmetric: for any non-null instances x and y of type AnyRef, x.eq(y) returns true if and
only if y.eq(x) returns true.
* It is transitive: for any non-null instances x, y, and z of type AnyRef if x.eq(y) returns true and y.eq(z) returns true, then x.eq(z) returns true.
Additionally, the eq method has three other properties.
* It is consistent: for any non-null instances x and y of type AnyRef, multiple invocations of
x.eq(y) consistently returns true or consistently returns false.
* For any non-null instance 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).
the object to compare against this object for reference equality.
true if the argument is a reference to the receiver object; false otherwise.
The equality method defined in AnyRef.
Tests whether every element of this stream relates to the corresponding element of another sequence by satisfying a test predicate.
Tests whether every element of this stream relates to the corresponding element of another sequence by satisfying a test predicate.
the type of the elements of that
the other sequence
true if both sequences have the same length and
p(x, y) is true for all corresponding elements x of this stream
and y of that, otherwise false.
use corresponds instead
Tests whether a predicate holds for some of the elements of this stream.
Tests whether a predicate holds for some of the elements of this stream.
Note: may not terminate for infinite-sized collections.
the predicate used to test elements.
true if the given predicate p holds for some of the elements
of this stream, otherwise false.
Returns all the elements of this stream that satisfy the
predicate p.
Returns all the elements of this stream that satisfy the
predicate p. The order of the elements is preserved.
the predicate used to filter the stream.
the elements of this stream satisfying p.
Selects all elements of this stream which do not satisfy a predicate.
Selects all elements of this stream which do not satisfy a predicate.
the predicate used to test elements.
a new stream consisting of all elements of this stream that do not satisfy the given
predicate p. The order of the elements is preserved.
This method is called by the garbage collector on the receiver object when garbage collection determines that there are no more references to the object.
This method is called by the garbage collector on the receiver object when garbage collection determines that there are no more references to the object.
The details of when and if the finalize method are invoked, as well as the interaction between finalizeand non-local returns and exceptions, are all platform dependent.
Finds the first element of the stream satisfying a predicate, if any.
Finds the first element of the stream satisfying a predicate, if any.
Note: may not terminate for infinite-sized collections.
the predicate used to test elements.
an option value containing the first element in the stream
that satisfies p, or None if none exists.
Returns index of the first element satisfying a predicate, or -1.
Returns index of the first element satisfying a predicate, or -1.
Returns index of the last element satisfying a predicate, or -1.
Returns index of the last element satisfying a predicate, or -1.
use lastIndexWhere instead
use head' instead
None if iterable is empty.
Applies the given function f to each element of
this stream, then concatenates the results.
Applies the given function f to each element of
this stream, then concatenates the results.
the element type of the returned collection.
the class of the returned collection. Where possible, That is
the same class as the current collection class Repr, but this
depends on the element type B being admissible for that class,
which means that an implicit instance of type CanBuildFrom[Repr, B, That] is found.
the function to apply on each 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.
f(a0) ::: ... ::: f(an) if
this stream is [a0, ..., an].
[use case] Converts this stream of traversable collections into a stream in which all element collections are concatenated.
Converts this stream of traversable collections into a stream in which all element collections are concatenated.
the type of the elements of each traversable collection.
a new stream resulting from concatenating all element streams.
Converts this stream of traversable collections into a stream in which all element collections are concatenated.
Converts this stream of traversable collections into a stream in which all element collections are concatenated.
the type of the elements of each traversable collection.
an implicit conversion which asserts that the element type of this
stream is a Traversable.
a new stream resulting from concatenating all element streams.
Stream specialization of foldLeft which allows GC to collect along the way.
Stream specialization of foldLeft which allows GC to collect along the way.@param z the start value.
the result type of the binary operator.
the binary operator.
the result of inserting op between consecutive elements of this stream,
going left to right with the start value z on the left:
op(...op(z, x1), x2, ..., xn)
where x,,1,,, ..., x,,n,, are the elements of this stream.
Applies a binary operator to all elements of this stream and a start value, going right to left.
Applies a binary operator to all elements of this stream and a start value, going right to left.
Note: will not terminate for infinite-sized collections.
the result type of the binary operator.
the start value.
the result of inserting op between consecutive elements of this stream,
going right to left with the start value z on the right:
op(x1, op(x2, ... op(xn, z)...))
where x,,1,,, ..., x,,n,, are the elements of this stream.
Tests whether a predicate holds for all elements of this stream.
Tests whether a predicate holds for all elements of this stream.
Note: may not terminate for infinite-sized collections.
the predicate used to test elements.
true if the given predicate p holds for all elements
of this stream, otherwise false.
Forces evaluation of the whole stream and returns it.
Forces evaluation of the whole stream and returns it.
Apply the given function f to each element of this linear sequence
(while respecting the order of the elements).
Apply the given function f to each element of this linear sequence
(while respecting the order of the elements).
the treatment to apply to each element.
The generic builder that builds instances of Stream at arbitrary element types.
The generic builder that builds instances of Stream at arbitrary element types.
Returns a representation that corresponds to the dynamic class of the receiver object.
Returns 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.
Partitions this stream into a map of streams according to some discriminator function.
Partitions this stream into a map of streams 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 stream.
the type of keys returned by the discriminator function.
the discriminator function.
A map from keys to streams 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 stream of those elements x for which f(x) equals k.
Partitions elements in fixed size streams.
Partitions elements in fixed size streams.
the number of elements per group
An iterator producing streams of size size, except the
last will be truncated if the elements don't divide evenly.
Iterator#grouped
Tests whether this stream is known to have a finite size.
Tests whether this stream 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 Stream produce a value from the hashcodes of all the elements of the stream.
Hashcodes for Stream produce a value from the hashcodes of all the elements of the stream.@return the hash code value for the object. */
The first element of this stream
The first element of this stream
Optionally selects the first element.
Optionally selects the first element.
the first element of this stream if it is nonempty, None if it is empty.
[use case] Finds index of first occurrence of some value in this stream after or at some start index.
Finds index of first occurrence of some value in this stream after or at some start index.
the element value to search for.
the start index
the index >= from of the first element of this stream that is equal (wrt ==)
to elem, or -1, if none exists.
Finds index of first occurrence of some value in this stream after or at some start index.
Finds index of first occurrence of some value in this stream after or at some start index.
Note: may not terminate for infinite-sized collections.
the type of the element elem.
the element value to search for.
the start index
the index >= from of the first element of this stream that is equal (wrt ==)
to elem, or -1, if none exists.
[use case] Finds index of first occurrence of some value in this stream.
Finds index of first occurrence of some value in this stream.
the element value to search for.
the index of the first element of this stream that is equal (wrt ==)
to elem, or -1, if none exists.
Finds index of first occurrence of some value in this stream.
Finds index of first occurrence of some value in this stream.
Note: may not terminate for infinite-sized collections.
the type of the element elem.
the element value to search for.
the index of the first element of this stream that is equal (wrt ==)
to elem, or -1, if none exists.
Finds first index after or at a start index where this stream contains a given sequence as a slice.
Finds first index after or at a start index where this stream contains a given sequence as a slice.
Note: may not terminate for infinite-sized collections.
the sequence to test
the start index
the first index >= from such that the elements of this stream starting at this index
match the elements of sequence that, or -1 of no such subsequence exists.
Finds first index where this stream contains a given sequence as a slice.
Finds first index where this stream contains a given sequence as a slice.
Note: may not terminate for infinite-sized collections.
the sequence to test
the first index such that the elements of this stream 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.
Note: may not terminate for infinite-sized collections.
the predicate used to test elements.
the start index
the index >= from of the first element of this stream 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.
Note: may not terminate for infinite-sized collections.
the predicate used to test elements.
the index of the first element of this stream 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 stream.
The stream without its last element.
The stream without its last element.
[use case] Computes the multiset intersection between this stream and another sequence.
Computes the multiset intersection between this stream and another sequence.
Note: may not terminate for infinite-sized collections.
the sequence of elements to intersect with.
a new stream which contains all elements of this stream
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.
Computes the multiset intersection between this stream and another sequence.
Computes the multiset intersection between this stream and another sequence.
Note: may not terminate for infinite-sized collections.
the element type of the returned stream.
the sequence of elements to intersect with.
a new collection of type That which contains all elements of this stream
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 stream contains given index.
Tests whether this stream contains given index.
The implementations of methods apply and isDefinedAt turn a Seq[A] into
a PartialFunction[Int, A].
true if this stream contains an element at position idx, false otherwise.
is this stream empty?@return true if the stream contain no elements, false otherwise.
is this stream empty?@return true if the stream contain no elements, false otherwise.
This method is used to test whether the dynamic type of the receiver object is T0.
This method is used to test whether the dynamic type of the receiver object is T0.
Note that the test result of the test is modulo Scala's erasure semantics. Therefore the expression1.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 requested typed.
true if the receiver object is an instance of erasure of type T0; false otherwise.
Tests whether this stream can be repeatedly traversed.
Tests whether this stream 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 first element of this stream.
[use case] Finds index of last occurrence of some value in this stream before or at a given end index.
Finds index of last occurrence of some value in this stream 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 stream that is equal (wrt ==)
to elem, or -1, if none exists.
Finds index of last occurrence of some value in this stream before or at a given end index.
Finds index of last occurrence of some value in this stream before or at a given end index.
the type of the element elem.
the element value to search for.
the end index.
the index <= end of the last element of this stream that is equal (wrt ==)
to elem, or -1, if none exists.
[use case] Finds index of last occurrence of some value in this stream.
Finds index of last occurrence of some value in this stream.
the element value to search for.
the index of the last element of this stream that is equal (wrt ==)
to elem, or -1, if none exists.
Finds index of last occurrence of some value in this stream.
Finds index of last occurrence of some value in this stream.
Note: will not terminate for infinite-sized collections.
the type of the element elem.
the element value to search for.
the index of the last element of this stream that is equal (wrt ==)
to elem, or -1, if none exists.
Finds last index before or at a given end index where this stream contains a given sequence as a slice.
Finds last index before or at a given end index where this stream contains a given sequence as a slice.
the sequence to test
the end index
the last index <= end such that the elements of this stream starting at this index
match the elements of sequence that, or -1 of no such subsequence exists.
Finds last index where this stream contains a given sequence as a slice.
Finds last index where this stream contains a given sequence as a slice.
Note: will not terminate for infinite-sized collections.
the sequence to test
the last index such that the elements of this stream 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 stream 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.
Note: will not terminate for infinite-sized collections.
the predicate used to test elements.
the index of the last element of this stream 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 stream$ if it is nonempty, None if it is empty.
The length of the stream.
The length of the stream.
Note: will not terminate for infinite-sized collections.
Note: the execution of length may take time proportial to the length of the sequence.@return the number of elements in this stream.
Compares the length of this stream to a test value.
Compares the length of this stream 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 an plain function returning an Option result.
Turns this partial function into an 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.
Returns the stream resulting from applying the given function
f to each element of this stream.
Returns the stream resulting from applying the given function
f to each element of this stream.
the element type of the returned collection.
the class of the returned collection. Where possible, That is
the same class as the current collection class Repr, but this
depends on the element type B being admissible for that class,
which means that an implicit instance of type CanBuildFrom[Repr, B, That] is found.
function to apply to each 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.
f(a0), ..., f(an) if this
sequence is a0, ..., an.
[use case] Finds the largest element.
Finds the largest element.
the largest element of this stream.
Finds the largest element.
Finds the largest element.
The type over which the ordering is defined.
An ordering to be used for comparing elements.
the largest element of this stream with respect to the ordering cmp.
[use case] Finds the smallest element.
Finds the smallest element.
the smallest element of this stream
Finds the smallest element.
Finds the smallest element.
The type over which the ordering is defined.
An ordering to be used for comparing elements.
the smallest element of this stream with respect to the ordering cmp.
Displays all elements of this stream in a string.
Displays all elements of this stream in a string.
a string representation of this stream. In the resulting string
the string representations (w.r.t. the method toString)
of all elements of this stream follow each other without any separator string.
Displays all elements of this stream in a string using a separator string.
Displays all elements of this stream in a string using a separator string.
the separator string.
a string representation of this stream. In the resulting string
the string representations (w.r.t. the method toString)
of all elements of this stream are separated by the string sep.
Displays all elements of this stream in a string using start, end, and separator strings.
Displays all elements of this stream in a string using start, end, and separator strings.
the starting string.
the separator string.
the ending string.
a string representation of this stream. 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 stream are separated by the string sep.
o.ne(arg0) is the same as !(o.eq(arg0)).
o.ne(arg0) is the same as !(o.eq(arg0)).
the object to compare against this object for reference dis-equality.
false if the argument is not a reference to the receiver object; true otherwise.
The builder that builds instances of type Stream[A]
The builder that builds instances of type Stream[A]
Tests whether the stream is not empty.
Tests whether the stream is not empty.
true if the stream 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.
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.
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.
Returns a new sequence of given length containing the elements of this sequence followed by zero or more occurrences of given elements.
Returns a new sequence of given length containing the elements of this sequence followed by zero or more occurrences of given elements.@param len the target length
the element type of the returned stream.
the class of the returned collection. Where possible, That is
the same class as the current collection class Repr, but this
depends on the element type B being admissible for that class,
which means that an implicit instance of type CanBuildFrom[Repr, B, That] is found.
the padding value
an implicit value of class CanBuildFrom which determines the
result class That from the current representation type Repr and the new element type B.
a new collection of type That consisting of
all elements of this stream followed by the minimal number of occurrences of elem so
that the resulting collection has a length of at least len.
Returns all the elements of this stream that satisfy the
predicate p.
Returns all the elements of this stream that satisfy the
predicate p. The order of the elements is preserved.
the predicate used to filter the stream.
the elements of this stream satisfying p.
[use case] Produces a new stream where a slice of elements in this stream is replaced by another sequence.
Produces a new stream where a slice of elements in this stream is replaced by another sequence.
the index of the first replaced element
the number of elements to drop in the original stream
a new stream consisting of all elements of this stream
except that replaced elements starting from from are replaced
by patch.
Produces a new stream where a slice of elements in this stream is replaced by another sequence.
Produces a new stream where a slice of elements in this stream is replaced by another sequence.
the element type of the returned stream.
the class of the returned collection. Where possible, That is
the same class as the current collection class Repr, but this
depends on the element type B being admissible for that class,
which means that an implicit instance of type CanBuildFrom[Repr, B, That] is found.
the index of the first replaced element
the replacement sequence
the number of elements to drop in the original stream
an implicit value of class CanBuildFrom which determines the
result class That from the current representation type Repr and the new element type B.
a new stream consisting of all elements of this stream
except that replaced elements starting from from are replaced
by patch.
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.
Note: may not terminate for infinite-sized collections.
the predicate used to test elements.
the length of the longest prefix of this stream
such that every element of the segment satisfies the predicate p.
Prints elements of this stream one by one, separated by sep.
Prints elements of this stream one by one, separated by sep.
The separator string printed between consecutive elements.
Prints elements of this stream one by one, separated by commas.
Prints elements of this stream one by one, separated by commas.
[use case] Multiplies up the elements of this collection.
Multiplies up the elements of this collection.
the product of all elements in this stream 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 stream and as result type of product.
Examples of such types are: Long, Float, Double, BigInt.
Multiplies up the elements of this collection.
Multiplies up the elements of this collection.
the result type of the * operator.
an implicit parameter defining a set of numeric operations
which includes the * operator to be used in forming the product.
the product of all elements of this stream with respect to the * operator in num.
returns a projection that can be used to call non-strict filter,map, and flatMap methods that build projections
of the collection.
returns a projection that can be used to call non-strict filter,map, and flatMap methods that build projections
of the collection.
use view' instead
Applies a binary operator to all elements of this stream, going left to right.
Applies a binary operator to all elements of this stream, going left to right.
Note: will not terminate for infinite-sized collections.
the result type of the binary operator.
the result of inserting op between consecutive elements of this stream,
going left to right:
op(...(op(x1, x2), ... ) , xn)
where x,,1,,, ..., x,,n,, are the elements of this stream.
Optionally applies a binary operator to all elements of this stream, going left to right.
Optionally applies a binary operator to all elements of this stream, going left to right.
Note: will not terminate for infinite-sized collections.
the result type of the binary operator.
the binary operator.
an option value containing the result of reduceLeft(op) is this stream is nonempty,
None otherwise.
Applies a binary operator to all elements of this stream, going right to left.
Applies a binary operator to all elements of this stream, going right to left.
Note: will not terminate for infinite-sized collections.
the result type of the binary operator.
the binary operator.
the result of inserting op between consecutive elements of this stream,
going right to left:
op(x1, op(x2, ..., op(xn-1, xn)...))
where x,,1,,, ..., x,,n,, are the elements of this stream.
Optionally applies a binary operator to all elements of this stream, going right to left.
Optionally applies a binary operator to all elements of this stream, going right to left.
Note: will not terminate for infinite-sized collections.
the result type of the binary operator.
the binary operator.
an option value containing the result of reduceRight(op) is this stream is nonempty,
None otherwise.
The collection of type stream underlying this TraversableLike object.
The collection of type stream underlying this TraversableLike object.
By default this is implemented as the TraversableLike object itself, but this can be overridden.
A list consisting of all elements of this list in reverse order.
An iterator yielding elements in reversed order.
An iterator yielding elements in reversed order.
Note: will not terminate for infinite-sized collections.
Note: xs.reverseIterator is the same as xs.reverse.iterator but might be more efficient.
an iterator yielding the elements of this stream in reversed order
[use case] Builds a new collection by applying a function to all elements of this stream and collecting the results in reversed order.
Builds a new collection by applying a function to all elements of this stream and collecting the results in reversed order.
the element type of the returned collection.
Note: xs.reverseMap(f) is the same as xs.reverse.map(f) but might be more efficient.
the function to apply to each element.
a new stream resulting from applying the given function
f to each element of this stream and collecting the results in reversed order.
Builds a new collection by applying a function to all elements of this stream and collecting the results in reversed order.
Builds a new collection by applying a function to all elements of this stream and collecting the results in reversed order.
Note: will not terminate for infinite-sized collections.
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 class of the returned collection. Where possible, That is
the same class as the current collection class Repr, but this
depends on the element type B being admissible for that class,
which means that an implicit instance of type CanBuildFrom[Repr, B, That] is found.
the function to apply to each 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.
a new collection of type That resulting from applying the given function
f to each element of this stream and collecting the results in reversed order.
use reverseIterator' instead
[use case] Checks if the other iterable collection contains the same elements in the same order as this stream.
Checks if the other iterable collection contains the same elements in the same order as this stream.
the collection to compare with.
true, if both collections contain the same elements in the same order, false otherwise.
Checks if the other iterable collection contains the same elements in the same order as this stream.
Checks if the other iterable collection contains the same elements in the same order as this stream.
Note: will not terminate for infinite-sized collections.
the type of the elements of collection that.
the collection to compare with.
true, if both collections contain the same elements in the same order, false otherwise.
Create a new stream which contains all intermediate results of applying the operator to subsequent elements left to right.
Create a new stream which contains all intermediate results of applying the operator to subsequent elements left to right.
the type of the elements in the resulting collection
the actual type of the resulting collection
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.
collection with intermediate results
Produces a collection containing cummulative results of applying the operator going right to left.
Produces a collection containing cummulative results of applying the operator going right to left.
Note: will not terminate for infinite-sized collections.
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.
collection with intermediate results
Computes length of longest segment whose elements all satisfy some predicate.
Computes length of longest segment whose elements all satisfy some predicate.
Note: may not terminate for infinite-sized collections.
the predicate used to test elements.
the index where the search starts.
the length of the longest segment of this stream starting from index from such that every element of the segment satisfies the predicate p.
The size of this stream, equivalent to length.
The size of this stream, equivalent to length.
Note: will not terminate for infinite-sized collections.@return the number of elements in this stream.
A substream starting at index from and extending up to (but not including) index until.
A substream starting at index from and extending up to (but not including) index until.
The index of the first element of the returned subsequence
The index of the element following the returned subsequence
a stream containing the elements starting at index from and extending up to (but not including) index until of this stream.@throws IndexOutOfBoundsException if from < 0 or length < from + len
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 streams of size size, except the
last will be truncated if the elements don't divide evenly.
Iterator#sliding
Sorts this Stream according to the Ordering which results from transforming an implicitly given Ordering with a transformation function.
Sorts this Stream 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 stream consisting of the elements of this stream
sorted according to the ordering where x < y if
ord.lt(f(x), f(y)).
scala.math.Ordering
Note: will not terminate for infinite-sized collections.
Sorts this stream according to a comparison function.
Sorts this stream according to a comparison function.
Note: will not terminate for infinite-sized collections.
The sort is stable. That is, elements that are equal wrt 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 stream consisting of the elements of this stream
sorted according to the comparison function lt.
Sorts this stream according to an Ordering.
Sorts this stream according to an Ordering.
The sort is stable. That is, elements that are equal wrt lt appear in the
same order in the sorted sequence as in the original.
the ordering to be used to compare elements.
a stream consisting of the elements of this stream
sorted according to the ordering ord.
scala.math.Ordering
Splits this stream into a prefix/suffix pair according to a predicate.
Splits this stream 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.
the test predicate
a pair consisting of the longest prefix of this stream whose
elements all satisfy p, and the rest of this stream.
Splits this stream into two at a given position.
Splits this stream 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 streams consisting of the first n elements of this stream, and the other elements.
Tests whether this stream starts with the given sequence.
Tests whether this stream starts with the given sequence.
the sequence to test
true if this collection has that as a prefix, false otherwise.
Tests whether this stream contains the given sequence at a given index.
Tests whether this stream contains the given sequence at a given index.
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 stream at index offset,
otherwise false.
Defines the prefix of this object's toString representation as Stream.@return a string representation which starts the result of toString applied to this stream.
By default the string prefix is the simple name of the collection class stream.
Defines the prefix of this object's toString representation as Stream.@return a string representation which starts the result of toString applied to this stream.
By default the string prefix is the simple name of the collection class stream.
[use case] Sums up the elements of this collection.
Sums up the elements of this collection.
the sum of all elements in this stream 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 stream and as result type of sum.
Examples of such types are: Long, Float, Double, BigInt.
Sums up the elements of this collection.
Sums up the elements of this collection.
the result type of the + operator.
an implicit parameter defining a set of numeric operations
which includes the + operator to be used in forming the sum.
the sum of all elements of this stream with respect to the + operator in num.
A stream consisting of the remaining elements of this stream after the first one.
A stream consisting of the remaining elements of this stream after the first one.
Is the tail of this stream defined?
Returns the n first elements of this stream, or else the whole
stream, if it has less than n elements.
Returns the n first elements of this stream, or else the whole
stream, if it has less than n elements.
the number of elements to take.
the n first elements of this stream.
Returns the rightmost n elements from this iterable.
Returns the rightmost n elements from this iterable.
the number of elements to take@return a stream consisting only of the last n elements of this stream, or else the
whole stream, if it has less than n elements.
Returns the longest prefix of this stream whose elements satisfy
the predicate p.
Returns the longest prefix of this stream whose elements satisfy
the predicate p.
the test predicate.@return the longest prefix of this stream whose elements all satisfy
the predicate p.
The underlying collection seen as an instance of Stream.
The underlying collection seen as an instance of Stream.
By default this is implemented as the current collection object itself,
but this can be overridden.
[use case] Converts this stream to an array.
Converts this stream to an array.
Note: will not terminate for infinite-sized collections.
an array containing all elements of this stream.
A ClassManifest must be available for the element type of this stream.
Converts this stream to an array.
Converts this stream to an array.
Note: will not terminate for infinite-sized collections.
the type of the elements of the array. A ClassManifest for this type must
be available.
an array containing all elements of this stream.
Converts this stream to a mutable buffer.
Converts this stream to a mutable buffer.
Note: will not terminate for infinite-sized collections.
a buffer containing all elements of this stream.
A conversion from collections of type Repr to Stream objects.
A conversion from collections of type Repr to Stream objects.
By default this is implemented as just a cast, but this can be overridden.
Converts this stream to an indexed sequence.
Converts this stream to an indexed sequence.
Note: will not terminate for infinite-sized collections.
an indexed sequence containing all elements of this stream.
Converts this stream to an iterable collection.
Converts this stream to an iterable collection.
Note: will not terminate for infinite-sized collections.
an Iterable containing all elements of this stream.
Returns an Iterator over the elements in this stream.
Returns an Iterator over the elements in this stream. Will return the same Iterator if this instance is already an Iterator.
Note: will not terminate for infinite-sized collections.
an Iterator containing all elements of this stream.
Converts this stream to a list.
Converts this stream to a list.
Note: will not terminate for infinite-sized collections.
a list containing all elements of this stream.
Converts this stream to a map.
Converts this stream to a map. This method is unavailable unless the elements are members of Tuple2, each ((K, V)) 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.
Note: will not terminate for infinite-sized collections.
a map containing all elements of this stream.
Converts this stream to a sequence.
Converts this stream to a sequence.
Note: will not terminate for infinite-sized collections.
Overridden for efficiency.@return a sequence containing all elements of this stream.
Converts this stream to a set.
Converts this stream to a set.
Note: will not terminate for infinite-sized collections.
a set containing all elements of this stream.
Converts this stream to a stream.
Converts this stream to a stream.
Note: will not terminate for infinite-sized collections.
a stream containing all elements of this stream.
Converts this stream to a string.
Converts this stream to a string.
a string representation of this collection. By default this
string consists of the stringPrefix of this stream,
followed by all elements separated by commas and enclosed in parentheses.
Converts this stream to an unspecified Traversable.
Converts this stream to an unspecified Traversable. Will return the same collection if this instance is already Traversable.
Note: will not terminate for infinite-sized collections.
a Traversable containing all elements of this stream.
Transposes this stream of traversable collections into a stream of streams.
Transposes this stream of traversable collections into a stream of streams.
the type of the elements of each traversable collection.
an implicit conversion which asserts that the element type of this
stream is a Traversable.
a two-dimensional stream of streams which has as nth row the nth column of this stream.
[use case] Produces a new sequence which contains all elements of this stream and also all elements of a given sequence.
Produces a new sequence which contains all elements of this stream and also all elements of
a given sequence. xs union ys is equivalent to xs ++ ys.
Note: will not terminate for infinite-sized collections.
the sequence to add.
a new stream which contains all elements of this stream
followed by all elements of that.
Produces a new sequence which contains all elements of this stream and also all elements of a given sequence.
Produces a new sequence which contains all elements of this stream and also all elements of
a given sequence. xs union ys is equivalent to xs ++ ys.
Note: will not terminate for infinite-sized collections.
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.
Note: will not terminate for infinite-sized collections.
the element type of the returned stream.
the class of the returned collection. Where possible, That is
the same class as the current collection class Repr, but this
depends on the element type B being admissible for that class,
which means that an implicit instance of type CanBuildFrom[Repr, B, That] is found.
the sequence to add.
an implicit value of class CanBuildFrom which determines the
result class That from the current representation type Repr and the new element type B.
a new collection of type That which contains all elements of this stream
followed by all elements of that.
Converts this stream of pairs into two collections of the first and second halfs of each pair.
Converts this stream of pairs into two collections of the first and second halfs of each pair.
an implicit conversion which asserts that the element type of this stream is a pair.
a pair streams, containing the first, respectively second half of each element pair of this stream.
[use case] A copy of this stream with one single replaced element.
A copy of this stream with one single replaced element.
the position of the replacement
the replacing element
a copy of this stream with the element at position index replaced by elem.
A copy of this stream with one single replaced element.
A copy of this stream with one single replaced element.
the element type of the returned stream.
the class of the returned collection. Where possible, That is
the same class as the current collection class Repr, but this
depends on the element type B being admissible for that class,
which means that an implicit instance of type CanBuildFrom[Repr, B, That] is found.
the position of the replacement
the replacing 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.
a new stream which is a copy of this stream with the element at position index replaced by elem.
Creates a non-strict view of a slice of this stream.
Creates a non-strict view of a slice of this stream.
Note: the difference between view and slice is that view produces
a view of the current stream, whereas slice produces a new stream.
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 stream, starting at index from and extending up to (but not including) index until.
Creates a non-strict view of this stream.
Creates a non-strict view of this stream.
a non-strict view of this stream.
Creates a non-strict filter of this stream.
Creates a non-strict filter of this stream.
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 stream which
satisfy the predicate p.
Returns a stream formed from this stream and the specified stream
that by associating each element of the former with
the element at the same position in the latter.
Returns a stream formed from this stream and the specified stream
that by associating each element of the former with
the element at the same position in the latter.
If one of the two streams is longer than the other, its remaining elements are ignored.
the type of the first half of the returned pairs (this is always a supertype
of the collection's element type A).
the type of the second half of the returned pairs
the class of the returned collection. Where possible, That is
the same class as the current collection class Repr, but this
depends on the element type (A1, B) being admissible for that class,
which means that an implicit instance of type CanBuildFrom[Repr, (A1, B), That].
is found.
The iterable providing the second half of each result pair
an implicit value of class CanBuildFrom which determines the
result class That from the current representation type Repr and the new element type (A1, B).
Stream({a0,b0}, ...,
{amin(m,n),bmin(m,n))} when
Stream(a0, ..., am)
zip Stream(b0, ..., bn) is invoked.
[use case] Returns a stream formed from this stream and another iterable collection by combining corresponding elements in pairs.
Returns a stream formed from this stream 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 stream is shorter than that.
the element to be used to fill up the result if that is shorter than this stream.
a new stream containing pairs consisting of
corresponding elements of this stream and that. The length
of the returned collection is the maximum of the lengths of this stream and that.
If this stream is shorter than that, thisElem values are used to pad the result.
If that is shorter than this stream, thatElem values are used to pad the result.
Returns a stream formed from this stream and another iterable collection by combining corresponding elements in pairs.
Returns a stream formed from this stream 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 iterable providing the second half of each result pair
the element to be used to fill up the result if this stream is shorter than that.
the element to be used to fill up the result if that is shorter than this stream.
a new collection of type That containing pairs consisting of
corresponding elements of this stream and that. The length
of the returned collection is the maximum of the lengths of this stream and that.
If this stream is shorter than that, thisElem values are used to pad the result.
If that is shorter than this stream, thatElem values are used to pad the result.
Zips this iterable with its indices.
Zips this iterable with its indices. s.zipWithIndex is equivalent to
s zip s.indices@tparam A1 the type of the first half of the returned pairs (this is always a supertype
of the collection's element type A).
the class of the returned collection. Where possible, That is
the same class as the current collection class Repr, but this
depends on the element type (A1, Int) being admissible for that class,
which means that an implicit instance of type CanBuildFrom[Repr, (A1, Int), That].
is found.
A new collection of type That containing pairs consisting of all elements of this
stream paired with their index. Indices start at 0.