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Module StreamSource

Streams and parsers.

Sourcetype 'a t

The type of streams holding values of type 'a.

Sourceexception Failure

Raised by parsers when none of the first components of the stream patterns is accepted.

Sourceexception Error of string

Raised by parsers when the first component of a stream pattern is accepted, but one of the following components is rejected.

Stream builders

Sourceval from : (int -> 'a option) -> 'a Stream.t

Stream.from f returns a stream built from the function f. To create a new stream element, the function f is called with the current stream count. The user function f must return either Some <value> for a value or None to specify the end of the stream.

Do note that the indices passed to f may not start at 0 in the general case. For example, [< '0; '1; Stream.from f >] would call f the first time with count 2.

Sourceval of_list : 'a list -> 'a Stream.t

Return the stream holding the elements of the list in the same order.

Sourceval of_string : string -> char Stream.t

Return the stream of the characters of the string parameter.

Sourceval of_bytes : bytes -> char Stream.t

Return the stream of the characters of the bytes parameter.

  • since 4.02.0
Sourceval of_channel : Stdlib.in_channel -> char Stream.t

Return the stream of the characters read from the input channel.

Stream iterator

Sourceval iter : ('a -> unit) -> 'a Stream.t -> unit

Stream.iter f s scans the whole stream s, applying function f in turn to each stream element encountered.

Predefined parsers

Sourceval next : 'a Stream.t -> 'a

Return the first element of the stream and remove it from the stream.

Sourceval empty : 'a Stream.t -> unit

Return () if the stream is empty, else raise Stream.Failure.

Useful functions

Sourceval peek : 'a Stream.t -> 'a option

Return Some of "the first element" of the stream, or None if the stream is empty.

Sourceval junk : 'a Stream.t -> unit

Remove the first element of the stream, possibly unfreezing it before.

Sourceval count : 'a Stream.t -> int

Return the current count of the stream elements, i.e. the number of the stream elements discarded.

Sourceval npeek : int -> 'a Stream.t -> 'a list

npeek n returns the list of the n first elements of the stream, or all its remaining elements if less than n elements are available.