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Module Fragments


module Fragments: sig .. end
General literate module

This module provides low-level functions for doing structured data I/O.

exception Error of string
val sf : ('a, unit, string) Pervasives.format -> 'a
Data tags

type tag =
| T_LParen
| T_RParen
| T_LBrack
| T_RBrack
| T_LBrace
| T_RBrace
| T_Equal
| T_Comma
| T_Semicolon
| T_Array
| T_Hashtbl
| T_Set 
val tags : tag list
List of all existing tags
val string_of_tag : tag -> string
Functions for interconverting tags and purely alphabetical lowercase strings
val tag_of_string : string -> tag
val int_of_tag : tag -> int
Functions for interconverting tags and integers between 0 and max_tag
val tag_of_int : int -> tag
val max_tag : int
Note that in order to reserver space for future tags, max_tag can be higher than the number of existing tags.
val is_start_tag : tag -> bool
Suggest open a pretty-printing box
val is_end_tag : tag -> bool
Suggest to close a pretty-printing box

type token =
| Bool of bool
| Char of char
| Int of int
| Int64 of int64
| Float of float
| String of string
| Tag of tag
| Field of string
| Constructor of string
| EOF
Tokens used by the lower-level I/O functions
val string_of_token : token -> string
Build a string representation of a token (usually for debugging)
type io_in
The type of input channels
type io_out
The type of output channels
val string_of_token : token -> string
val create_io_in : read_token:(unit -> token) ->
       peek_token:(unit -> token) ->
       ?finish:(io_in -> unit -> unit) -> unit -> io_in
Create an input channel from the given functions
val flush : io_out -> unit
val is_word_reserved : string -> bool
Is this a reserved word, such as array, hash or set ?
val is_tag_voluminous : tag -> bool
Does this tag require space around it ?
val drop_token : io_in -> unit
On failure, the following functions raise an Error(...) exception containing a useful message.

Remove a token from an input channel

val peek_token : io_in -> token
Peek a token from an input channel
val read_token : io_in -> token
Read a token from an input channel
val read_tag : io_in -> tag
Read a tag token.
val read_this_tag : io_in -> tag -> unit
Read this particular tag.
val finish : io_in -> unit
Finish consuming the input. Actually, this matches the Stop_data tag.
val read_int : io_in -> int
Read an integer.
val read_int64 : io_in -> int64
Read a 64-bit integer.
val read_float : io_in -> float
Read a floating-point number.
val read_bool : io_in -> bool
Read a boolean.
val read_char : io_in -> char
Read a character.
val read_field : io_in -> string
Read a field label.
val read_constructor : io_in -> string
Read a constructor name.
val read_string : io_in -> string
Read a string.
val loss : io_in -> unit
Signal that some data has been lost. This will be called, for instance, if the reader sees an unknown record field name.
val lost : io_in -> bool
Tells us if any data has been lost, e.g., if loss has ever been called on this channel.
val create_io_out : write_token:(token -> unit) ->
       ?flush:(unit -> unit) -> unit -> io_out
Create an output channel from the given functions.
val write_token : io_out -> token -> unit
Write a token.
val write_int : io_out -> int -> unit
Write an integer.
val write_int64 : io_out -> int64 -> unit
Write a 64-bit integer.
val write_char : io_out -> char -> unit
Write a char.
val write_string : io_out -> string -> unit
Write a string.
val write_bool : io_out -> bool -> unit
Write a boolean.
val write_float : io_out -> float -> unit
Write a floating-point number.
val write_tag : io_out -> tag -> unit
Write a tag.
val write_field : io_out -> string -> unit
Write a fiel label.
val write_constructor : io_out -> string -> unit
Write a constructor name.