package reparse-lwt-unix

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Module Reparse_lwt_unix.ChannelSource

Channel is a Lwt_io.input_channel input based Reparse parser.

include Reparse.PARSER with type 'a promise = 'a Lwt.t
Sourcetype 'a t

Represents a parser which can parse value 'a. Use parse functions to evaluate a parser.

Sourcetype 'a promise = 'a Lwt.t
Sourcetype input
Sourceval parse : input -> 'a t -> ('a, string) result promise

Monadic operators

Sourceval return : 'a -> 'a t

return v always parses value v.

Examples

  module P = Reparse.String.String

  ;;
  let input = new P.string_input "" in
  let v1 = P.(parse input (return 5)) in
  let v2 = P.(parse input (return "hello")) in
  v1 = 5 && v2 = "hello"
Sourceval unit : unit t

unit always parses to ():unit value.

Sourceval ignore : _ t -> unit t

ignore p ignore any result from p upon success and return () instead.

Sourceval fail : string -> 'a t

fail err_msg returns a parser that always fails with err_msg.

Examples

  module P = Reparse.String

  ;;
  let input = new P.string_input "" in
  let r =
    try
      let _ = P.(parse input (fail "hello error")) in
      assert false
    with e -> e in
  r
  = P.Parser
      {offset= 0; line_number= 0; column_number= 0; msg= "hello error"}
Sourceval bind : ('a -> 'b t) -> 'a t -> 'b t

bind f p is prefix version of p >>= f.

Sourceval both : 'a t -> 'b t -> ('a * 'b) t

both p q is evaluates to (a,b) when a is evaluted from p and b is evaluated from q.

Sourceval apply : ('a -> 'b) t -> 'a t -> 'b t
Sourceval map : ('a -> 'b) -> 'a t -> 'b t

map f p is prefix version of p >>| f.

Sourceval map2 : ('a -> 'b -> 'c) -> 'a t -> 'b t -> 'c t
Sourceval map3 : ('a -> 'b -> 'c -> 'd) -> 'a t -> 'b t -> 'c t -> 'd t
Sourceval map4 : ('a -> 'b -> 'c -> 'd -> 'e) -> 'a t -> 'b t -> 'c t -> 'd t -> 'e t
Sourcemodule Infix : sig ... end
include module type of Infix
Sourceval (>>=) : 'a t -> ('a -> 'b t) -> 'b t

p >>= f returns a new parser b where,

  • a is the parsed value of p
  • b is f a Also known as bind operation.

Examples

  module P = Reparse.String
  open P

  ;;
  let f a = P.pure (Char.code a) in
  let p = P.char 'h' in
  let p = p >>= f in
  let v = P.parse_string p "hello" in
  v = 104
Sourceval (>>|) : 'a t -> ('a -> 'b) -> 'b t

p >>| f returns a new parser encapsulating value b where,

  • a is the parsed value of p.
  • b is f a. Also known as map operation.

Examples

  module P = Reparse.String
  open P

  ;;
  let f a = Char.code a in
  let p = P.char 'h' in
  let p = p >>| f in
  let v = P.parse_string p "hello" in
  v = 104
Sourceval (<*>) : 'a t -> ('a -> 'b) t -> 'b t

pf <*> q returns a new parser encapsulating value b where

  • pf and q are evaluated sequentially in order as given.
  • f is the parsed value of pf
  • a is the parsed value of q
  • b is f a Also known as Applicative operation.

Examples

  module P = Reparse
  open P

  ;;
  let f a = a + 2 in
  let pf = P.pure f in
  let q = P.pure 2 in
  let p = pf <*> q in
  let v = P.parse_string p "hello" in
  v = 4
Sourceval (<$>) : 'a t -> ('a -> 'b) -> 'b t

f <$> p is return f <*> p.

Sourceval (<$$>) : ('a t * 'b t) -> ('a -> 'b -> 'c) -> 'c t
Sourceval (<$$$>) : ('a t * 'b t * 'c t) -> ('a -> 'b -> 'c -> 'd) -> 'd t
Sourceval (<$$$$>) : ('a t * 'b t * 'c t * 'd t) -> ('a -> 'b -> 'c -> 'd -> 'e) -> 'e t
Sourceval (<$) : 'a -> 'b t -> 'a t

v <$ p replaces the parse value of p with v.

Examples

  module P = Reparse.String
  open P

  ;;
  let v = "hello" in
  let p = P.char 'h' in
  let p = v <$ p in
  let v2 = P.parse_string p "hello" in
  v2 = "hello"
Sourceval ($>) : 'a t -> 'b -> 'b t

p $> v is inverse of v <$ p.

Sourceval (*>) : _ t -> 'b t -> 'b t

p *> q returns a parser encapsulating value a where,

  • p, q are evaluated sequentially in order as given.
  • a is parsed value of q.
  • The parsed value of p is discarded. Also known as discard left.

Examples

  module P = Reparse.String
  open P

  ;;
  let p = P.string "world" in
  let q = P.pure "hello" in
  let p = p *> q in
  let v = P.parse_string p "world" in
  v = "hello"
Sourceval (<*) : 'a t -> _ t -> 'a t

p <* q returns a parser encapsulating value a where,

  • p, q are evaluated sequentially in order as given.
  • a is parsed value of p.
  • The parsed value of q is discarded. Also know as discard_right.

Examples

  module P = Reparse.String
  open P

  ;;
  let p = P.string "world" in
  let q = P.pure "hello" in
  let p = p <* q in
  let v = P.parse_string p "world" in
  v = "world"
Sourceval (<|>) : 'a t -> 'a t -> 'a t

p <|> q returns a parser encapsulating value a where,

  • p,q are evaluated sequentially in order as given.
  • a is the parsed value of p if p is successful
  • a is the parsed value of q if p is a failure and q is a success.
  • If both - p and q - fails, then the parser fails.

Examples

p fails and q succeeds, therefore we return q's parsed value 'w'

  module P = Reparse.String
  open P

  ;;
  let p = P.char 'h' in
  let q = P.char 'w' in
  let p = p <|> q in
  let v = P.parse_string p "world" in
  v = 'w'

p succeeds therefore we return its parsed value 'h'

  let p = P.char 'h' in
  let q = P.char 'w' in
  let p = p <|> q in
  let v = P.parse_string p "hello" in
  v = 'h'

The parser fails if both p and q fails.

  let p = P.char 'h' in
  let q = P.char 'w' in
  let p = p <|> q in
  let v =
    try
      let _ = P.parse_string p "" in
      false
    with _ -> true in
  v = true
Sourceval (let*) : 'a t -> ('a -> 'b t) -> 'b t

let* is a let syntax binding for Reparse.Infix.((>>=))

Examples

  module P = Reparse.String
  open P

  ;;
  let p =
    let* a = P.pure 5 in
    let total = a + 5 in
    P.pure total in
  let v = P.parse_string p "" in
  v = 10
Sourceval (and*) : 'a t -> 'b t -> ('a * 'b) t
Sourceval (let+) : 'a t -> ('a -> 'b) -> 'b t

let* is a let syntax binding for Reparse.((>|=))

Examples

  module P = Reparse.String
  open P

  ;;
  let p =
    let+ a = P.pure 5 in
    let total = a + 5 in
    total in
  let v = P.parse_string p "" in
  v = 10
Sourceval (and+) : 'a t -> 'b t -> ('a * 'b) t
Sourceval (<?>) : 'a t -> string -> 'a t

p <?> err_msg parses p to value a and returns a new parser encapsulating a. If p is a failure, then it fails with error message err_msg. Often used as a last choice in <|>, e.g. a <|> b <|> c <?> "expected a b c".

Examples

  module P = Reparse.String
  open P

  ;;
  let p = P.char 'h' <|> P.char 'w' in
  let err_msg = "[error]" in
  let p = p <?> err_msg in
  let v =
    try
      let _ = P.parse_string p "" in
      false
    with
    | P.Parser
        {offset= 0; line_number= 0; column_number= 0; msg= "[error]"} ->
        true
    | _ -> false in
  v = true
Sourcemodule Let_syntax : sig ... end

ppx_let syntax support module.

Char/String parsers

Sourceval peek_char : char t

peek_char t parses the next character from input without consuming it. It fails if EOI is reached.

Examples

  module P = Reparse.String

  ;;
  let p = P.peek_char in
  let v = P.parse_string p "hello" in
  v = 'h'

Input is not consumed.

Sourceval peek_char_opt : char option t

peek_char_opt is the exception safe version of peek_char. It returns an option rather than throwing exn when EOI is reached.

Sourceval peek_string : int -> string t

peek_string n parse a string of length n without consuming it.

Examples

  module P = Reparse.String
  open P

  ;;
  let p = P.peek_string 5 in
  let v = P.parse_string p "hello" in
  v = "hello"

Input is not consumed.

Sourceval any_char : char t

any_char parses the next character from input. Fails if input has reached end of input.

Examples

  module P = Reparse.String

  ;;
  let v = P.(parse_string any_char "hello") in
  v = 'h'
Sourceval unsafe_any_char : char t

unsafe_any_char is same as any_char except the returned char value is not buffered by the input. Important don't use this parser with backtracking parsers such as <|>, alt, any etc.

Note Ensure you call trim_input_buffer after calling this parser.

Sourceval char : char -> char t

char c parses character c exactly.

Examples

  module P = Reparse.String

  ;;
  let p = P.char 'h' in
  let v = P.parse_string p "hello" in
  v = 'h'
Sourceval char_if : (char -> bool) -> char t

char_if f parses a character c if f c is true.

Examples

  module P = Reparse.String

  ;;
  let p = P.char_if (function 'a' -> true | _ -> false) in
  let v = P.parse_string p "abc" in
  v = 'a'
Sourceval string_cs : string -> string t

string_cs s parses a string s exactly. String comparison is case sensitive.

Examples

  module P = Reparse.String

  ;;
  let p = P.string_cs "hello" in
  let v = P.parse p (P.of_string "hello world") in
  v = "hello"
Sourceval string_ci : string -> string t
Sourceval string_of_chars : char list -> string t

string_of_chars l converts char list l to string

Examples

  module P = Reparse.String

  ;;
  let p = P.(take ~sep_by:space next >>= string_of_chars) in
  let v = P.parse_string p "h e l l o" in
  v = "hello"
Sourceval take_string : int -> string t

take_string n returns a string of length n exactly from input.

Sourceval take_cstruct : int -> Cstruct.t t

take_cstruct n returns a Cstruct.t of length n exactly from input. This is usually a zeor copy - depending on input of course - version of take_string.

Alternate parsers

Sourceval any : ?failure_msg:string -> 'a t list -> 'a t

any l parses the value of the first successful parser in list l. Specified parsers in l are evaluated sequentially from left to right. A failed parser doesn't consume any input, i.e. offset is unaffected. The parser fails if none of the parsers in l are evaluated successfully.

Examples

First successful parser result is returned

  module P = Reparse.String

  ;;
  let p = P.(any [char 'z'; char 'x'; char 'a']) in
  let v = P.parse_string p "zabc" in
  v = 'z'

  ;;
  let p = P.(any [char 'z'; char 'x'; char 'a']) in
  let v = P.parse_string p "xabc" in
  v = 'x'

  ;;
  let p = P.(any [char 'z'; char 'x'; char 'a']) in
  let v = P.parse_string p "abc" in
  v = 'a'

Parser fails when none of the parsers in l are successful.

  let p = P.(any [char 'z'; char 'x'; char 'a']) in
  let v =
    try
      let _ = P.parse_string p "yyy" in
      false
    with _ -> true in
  v = true
Sourceval alt : 'a t -> 'a t -> 'a t

alt p q is p <|> q. See Reparse.Infix.((<|>))

Sourceval optional : 'a t -> 'a option t

optional p parses Some a if successful and None otherwise. a is the parsed value of p.

Examples

  module P = Reparse.String
  open P

  ;;
  let p = P.(optional (char 'a')) in
  let v = P.parse_string p "ab" in
  v = Some 'a'

  ;;
  let p = P.(optional (char 'z')) in
  let v = P.parse_string p "ab" in
  v = None

Boolean

Sourceval not_ : 'a t -> unit t

not_ p parses value () if and only if p fails to parse, otherwise the parse fails.

Examples

  module P = Reparse.String

  ;;
  let p = P.(not_ (char 'a')) in
  let v = P.parse_string p "bbb" in
  v = ()
Sourceval is : 'a t -> bool t

is p parses true if p is successful, false otherwise. Note evaluation of p doesn't consume any input.

Examples

  module P = Reparse.String

  ;;
  let p = P.(is (char 'b')) in
  let v = P.parse_string p "bcb" in
  v = true
Sourceval is_not : 'a t -> bool t

is_not p parses value true if p fails to parse and false otherwise. Note evaluating p doesn't consume any input.

Examples

  module P = Reparse.String

  ;;
  let p = P.(is_not (char 'a')) in
  let v = P.parse_string p "bbb" in
  v = true

Repetition

Sourceval recur : ('a t -> 'a t) -> 'a t

recur f returns a recursive parser. Function value f accepts a parser p as its argument and returns a parser q. Parser q in its definition can refer to p and p can refer to q in its own definition. Such parsers are also known as a fixpoint or y combinator.

Sourceval all : 'a t list -> 'a list t

all parsers parses all parsers in parsers and returns a list of successful parse result. All of the parsers must succeed for all to succeed.

Sourceval all_unit : _ t list -> unit t

all_unit parsers parses parsers and discards their results. All of the parsers must succeed for all_unit to succeed.

Sourceval skip : ?at_least:int -> ?up_to:int -> _ t -> int t

skip ~at_least ~up_to p repeatedly parses p and discards its value. The lower and upper bound of repetition is specified by arguments at_least and up_to respectively. The default value of at_least is 0. The default value of up_to is unspecified, i.e. there is no upper limit. The repetition ends when one of the following occurs:

  • p evaluates to failure
  • up_to upper bound value is reached The parser encapsulates the count of times p was evaluated successfully.

Examples

  module P = Reparse.String

  ;;
  let p = P.(skip space) in
  let v = P.parse_string p "     " in
  v = 5
Sourceval take : ?at_least:int -> ?up_to:int -> ?sep_by:_ t -> 'a t -> 'a list t

take ~at_least ~up_to ~sep_by p repeatedly parses p and returns the parsed values. The lower and upper bound of repetition is specified by arguments at_least and up_to respectively. The default value of at_least is 0. The default value of up_to is unspecified, i.e. there is no upper limit. If sep_by is specified then the evaluation of p must be followed by a successful evaluation of sep_by. The parsed value of sep_by is discarded. The repetition ends when one of the following occurs:

  • p evaluates to failure
  • sep_by evaluates to failure
  • up_to upper boudn value is reached The parser fails if the count of repetition of p does not match the value specified by at_least.

Examples

Default behaviour.

  module P = Reparse.String

  ;;
  let p = P.(take (char 'a')) in
  let v = P.parse_string p "aaaaa" in
  v = ['a'; 'a'; 'a'; 'a'; 'a']

Specify ~sep_by.

  module P = Reparse.String

  ;;
  let p = P.(take ~sep_by:(char ',') (char 'a')) in
  let v = P.parse_string p "a,a,a,a,a" in
  v = ['a'; 'a'; 'a'; 'a'; 'a']

Specify lower bound argument at_least.

  module P = Reparse.String

  ;;
  let p = P.(take ~at_least:3 ~sep_by:(char ',') (char 'a')) in
  let v = P.parse_string p "a,a,a,a,a" in
  v = ['a'; 'a'; 'a'; 'a'; 'a']

Lower bound not met results in error.

  module P = Reparse.String

  ;;
  let p = P.(take ~at_least:5 ~sep_by:(char ',') (char 'a')) in
  let v =
    try
      let _ = P.parse_string p "a,a,a,a" in
      false
    with _ -> true in
  v = true

Specify upper bound up_to.

  module P = Reparse.String

  ;;
  let p = P.(take ~up_to:3 ~sep_by:(char ',') (char 'a')) in
  let v = P.parse_string p "a,a,a,a,a" in
  v = ['a'; 'a'; 'a']
Sourceval take_while_cb : ?sep_by:_ t -> while_:bool t -> on_take_cb:('a -> unit t) -> 'a t -> unit t

take_while_cb ~sep_by ~while_ ~on_take p repeatedly parses p and calls callback on_take_cb with the parsed value. p is evaluated if and only if while_ evaluates to true. If sep_by is specified then the evaluation of p must be followed by a successful evaluation of sep_by. The parsed value of sep_by is discarded. p is evaluated repeatedly. The repetition ends when one of the following occurs: on_take_cb is the callback function that is called every time p is evaluated.

  • p evaluates to failure
  • while_ returns false
  • sep_by evaluates to failure take_while_cb is the general version of Reparse.take_while. It allows to specify how the value a is to be collected. Note while_ does not consume input.

Examples

  module P = Reparse.String
  open P

  ;;
  let buf = Buffer.create 0 in
  let on_take_cb a = Buffer.add_char buf a in
  let p =
    P.(take_while_cb (char 'a') ~while_:(is_not (char 'b')) ~on_take_cb)
  in
  let v = P.parse_string p "aaab" in
  let s = Buffer.contents buf in
  v = 3 && s = "aaa"
Sourceval take_while : ?sep_by:_ t -> while_:bool t -> 'a t -> 'a list t

take_while ~sep_by p ~while_ p repeatedly parses p and returns its value. p is evaluated if and only if while_ evaluates to true. If sep_by is specified then the evaluation of p must be followed by a successful evaluation of sep_by. The parsed value of sep_by is discarded. The repetition ends when one of the following occurs:

  • p evaluates to failure
  • while_ returns false
  • sep_by evaluates to failure Note while_ does not consume input.

Examples

Default behaviour.

  module P = Reparse.String

  ;;
  let p = P.(take_while ~while_:(is_not (char 'b')) (char 'a')) in
  let v = P.parse_string p "aab" in
  v = ['a'; 'a']

Specify sep_by.

  module P = Reparse.String

  ;;
  let p =
    P.(
      take_while ~sep_by:(char ',') ~while_:(is_not (char 'b')) (char 'a'))
  in
  let v = P.parse_string p "a,a,ab" in
  v = ['a'; 'a'; 'a']
Sourceval take_between : ?sep_by:_ t -> start:_ t -> end_:_ t -> 'a t -> 'a list t

take_between ~sep_by ~start ~end_ p parses start and then repeatedly parses p while the parsed value of p doesn't equal to parsed value of end_. After the repetition end, it parses end_. The parser returns the list of parsed values of p. Both start and end_ parser values are discarded. If sep_by is specified then the evaluation of p must be followed by a successful evaluation of sep_by. The parsed value of sep_by is discarded. The repetition ends when one of the following occurs:

  • p evaluates to failure
  • end_ parsed value matches p parsed value
  • sep_by evaluates to failure

Examples

  module P = Reparse.String

  ;;
  let p =
    P.(
      take_between ~sep_by:(char ',') ~start:(P.char '(') ~end_:(char ')')
        next) in
  let v = P.parse_string p "(a,a,a)" in
  v = ['a'; 'a'; 'a']

RFC 5234

Parsers as defined in RFC 5234, Appendix B.1.

Sourceval alpha : char t

alpha parses a character in range A- Z or a-z.

Examples

  module P = Reparse
  open P

  ;;
  let p = P.(take alpha) in
  let v = P.parse_string p "abcdABCD" in
  v = ['a'; 'b'; 'c'; 'd'; 'A'; 'B'; 'C'; 'D']
Sourceval alpha_num : char t

alpha_num parses a character in range A-Z or a-z or 0-9.

Examples

  module P = Reparse
  open P

  ;;
  let p = P.(take alpha_num) in
  let v = P.parse_string p "ab123ABCD" in
  v = ['a'; 'b'; '1'; '2'; '3'; 'A'; 'B'; 'C'; 'D']
Sourceval lower_alpha : char t

lower_alpha parses a character in range a-z.

Examples

  module P = Reparse
  open P

  ;;
  let p = P.(take lower_alpha) in
  let v = P.parse_string p "abcd" in
  v = ['a'; 'b'; 'c'; 'd']
Sourceval upper_alpha : char t

upper_alpha parses a character in range A-Z.

Examples

  module P = Reparse
  open P

  ;;
  let p = P.(take upper_alpha) in
  let v = P.parse_string p "ABCD" in
  v = ['A'; 'B'; 'C'; 'D']
Sourceval bit : char t

bit parses a character which is either '0' or '1'.

Examples

  module P = Reparse

  ;;
  let p = P.(take bit) in
  let v = P.parse_string p "0110 ab" in
  v = ['0'; '1'; '1'; '0']
Sourceval ascii_char : char t

ascii_char parses any US-ASCII character.

Examples

  module P = Reparse

  ;;
  let p = P.(take ascii_char) in
  let v = P.parse_string p "0110 abc '" in
  v = ['0'; '1'; '1'; '0'; ' '; 'a'; 'b'; 'c'; ' '; '\'']
Sourceval cr : char t

cr parses character '\r'.

Examples

  module P = Reparse

  ;;
  let v = P.(parse_string cr "\rab") in
  v = '\r'
Sourceval crlf : string t

crlf parses string "\r\n".

Examples

  module P = Reparse

  ;;
  let v = P.(parse_string crlf "\r\n abc") in
  v = "\r\n"
Sourceval control : char t

control parses characters in range 0x00 - 0x1F or character 0x7F.

Examples

  module P = Reparse

  ;;
  let v = P.(parse_string control "\x00") in
  v = '\x00'
Sourceval digit : char t

digit parses one of the digit characters, 0 .. 9.

Examples

  module P = Reparse

  ;;
  let p = P.(take digit) in
  let v = P.parse_string p "0123456789a" in
  v = ['0'; '1'; '2'; '3'; '4'; '5'; '6'; '7'; '8'; '9']
Sourceval digits : string t

digits parses one or more digit characters, 0 .. 9.

Examples

  module P = Reparse

  ;;
  let v = P.(parse_string digits "1234 +") in
  v = "1234"
Sourceval dquote : char t

dquote parses double quote character '"'.

Examples

  module P = Reparse

  ;;
  let v = P.(parse_string dquote "\"hello ") in
  v = '"'
Sourceval hex_digit : char t

hex_digit parses any of the hexadecimal digits - 0..9, A, B, C, D, E, F.

Examples

  module P = Reparse

  ;;
  let p = P.(take hex_digit) in
  let v = P.parse_string p "0ABCDEFa" in
  v = ['0'; 'A'; 'B'; 'C'; 'D'; 'E'; 'F']
Sourceval htab : char t

htab parses a horizontal tab character '\t'.

Examples

  module P = Reparse

  ;;
  let v = P.(parse_string htab "\t") in
  v = '\t'
Sourceval lf : char t

lf parses a linefeed '\n' character.

Examples

  module P = Reparse

  ;;
  let v = P.(parse_string lf "\n") in
  v = '\n'
Sourceval octet : char t

octect parses any character in the range \x00 - \xFF. Synonym for Reparse.next

Examples

  module P = Reparse

  ;;
  let p = P.(take octet) in
  let v = P.parse_string p "0110 abc '" in
  v = ['0'; '1'; '1'; '0'; ' '; 'a'; 'b'; 'c'; ' '; '\'']
Sourceval space : char t

space parses a space character.

Examples

  module P = Reparse

  ;;
  let v = P.(parse_string space " abc '") in
  v = ' '
Sourceval vchar : char t

vchar parses any of the visible - printable - characters.

Examples

  module P = Reparse

  ;;
  let p = P.(take vchar) in
  let v = P.parse_string p "0110abc\x00" in
  v = ['0'; '1'; '1'; '0'; 'a'; 'b'; 'c']
Sourceval whitespace : char t

whitespace parses a space ' ' or horizontal tab '\t' character.

Examples

  module P = Reparse

  ;;
  let p = P.(take whitespace) in
  let v = P.parse_string p "\t \t " in
  v = ['\t'; ' '; '\t'; ' ']

Input manipulation

Sourceval advance : int -> unit t

advance n advances input by n bytes.

Sourceval eoi : unit t

eoi parses end of input. Fails if parser is not at end of input.

Examples

  module P = Reparse.String

  ;;
  let v = P.(parse_string eoi "") in
  v = ()

  ;;
  let v =
    try
      let _ = P.(parse_string eoi "a") in
      false
    with _ -> true in
  v = true
Sourceval trim_input_buffer : unit t

trim_input_buffer () calls INPUT.trim_buffer with the current parser position. Use this function to control the memory consumption of the input buffer.

Note Once trimmed the parser is unable to backtrack beyond the position of last_trimmed_pos. This may affect a correct functioning of <|> parser as it backtracks when trying various alternatives.

Sourceval pos : int t

pos returns the current parser position.

Sourceval last_trimmed_pos : int t

last_trimmed_pos returns the last trimmed input position marker.

Sourceval input_buffer_size : int option t

input_buffer_size returns current input buffer size in bytes if input is a buffered input otherwise it returns None for unbuffered input.

Sourceval of_promise : 'a promise -> 'a t
Sourceval create_input : Lwt_io.input_channel -> input