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| Description |
| Streams are infinite lists. Most operations on streams are
completely analogous to the definition in Data.List.
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| Synopsis |
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| The type of streams
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| An infinite sequence.
| | Constructors | |  Instances | |
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| Basic functions
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| Extract the first element of the sequence.
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| Extract the sequence following the head of the stream.
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| Stream transformations
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| Apply a function uniformly over all elements of a sequence.
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| Building streams
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iterate f x function produces the infinite sequence
of repeated applications of f to x.
iterate f x = [x, f x, f (f x), ..]
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| repeat x returns a constant stream, where all elements are equal to x.
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cycle xs returns the infinite repetition of xs:
cycle [1,2,3] = Cons 1 (Cons 2 (Cons 3 (Cons 1 (Cons 2 ...
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| The unfold function is similar to the unfold for lists. Note there is no base case: all streams must be infinite.
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| Extracting sublists
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| take n xs returns the first n elements of xs.
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| The splitAt function takes an integer n and a stream xs
| and returns a pair consisting of the prefix of xs of length
| n and the remaining stream immediately following this prefix.
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drop n xs drops the first n elements off the front of the sequence xs.
takeWhile p xs returns the longest prefix of the stream xs for which the predicate p holds.
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| dropWhile p xs returns the suffix remaining after takeWhile p xs.
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| span p xs returns the longest prefix of xs that satisfies
p, together with the remainder of the stream.
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| The break p function is equivalent to span not . p.
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| filter p xs, removes any elements from xs that do not satisfy p.
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| The partition function takes a predicate p and a stream
xs, and returns a pair of streams. The first stream corresponds
to the elements of xs for which p holds; the second stream
corresponds to the elements of xs for which p does not hold.
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| Sublist predicates
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| The isPrefix function returns True if the first argument is a prefix of the second.
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| Indexing streams
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| xs !! n returns the element of the stream xs at index
n. Note that the head of the stream has index 0.
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| Zipping and unzipping streams
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| The zip function takes two streams and returns a list of corresponding pairs.
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| The zipWith function generalizes zip. Rather than tupling
the functions, the elements are combined using the function
passed as the first argument to zipWith.
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| The unzip function is the inverse of the zip function.
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| Functions on streams of characters
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| The words function breaks a stream of characters into a stream of words,
which were delimited by white space.
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| The unwords function is an inverse operation to words. It
joins words with separating spaces.
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| The lines function breaks a stream of characters into a list
of strings at newline characters. The resulting strings do not
contain newlines.
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| The unlines function is an inverse operation to lines. It
joins lines, after appending a terminating newline to each.
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| Converting to and from an infinite list
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| The listToStream converts an infinite list to a
stream. Passing a finite list will result in an error.
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| The streamToList converts a stream into an infinite list.
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| Produced by Haddock version 2.1.0 |
