package containers

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package containers
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IO Utils

Simple utilities to deal with basic Input/Output tasks in a resource-safe way. For advanced IO tasks, the user is advised to use something like Lwt or Async, that are far more comprehensive. This module depends on CCGen.

  • since 0.6

NOTE this was formerly a monadic IO module. The old module is now in containers.advanced under the name CCMonadIO.

Examples:

  • obtain the list of lines of a file:
# let l = CCIO.(with_in "/tmp/some_file" read_lines);;
  • transfer one file into another:
# CCIO.(
  with_in "/tmp/input"
    (fun ic ->
      with_out ~flags:[Open_creat] ~mode:0o644 "/tmp/output"
        (fun oc ->
          Seq.chunks 512 ic |> Seq.to_output oc
        )
    )
) ;;
type 'a gen = unit -> 'a option

See CCGen

Input

val with_in : ?mode:int -> ?flags:Pervasives.open_flag list -> string -> (Pervasives.in_channel -> 'a) -> 'a

Open an input file with the given optional flag list, calls the function on the input channel. When the function raises or returns, the channel is closed.

val read_chunks : ?size:int -> Pervasives.in_channel -> string gen

Read the channel's content into chunks of size size

val read_line : Pervasives.in_channel -> string option

Read a line from the channel. Returns None if the input is terminated. The "\n" is removed from the line.

val read_lines : Pervasives.in_channel -> string gen

Read all lines. The generator should be traversed only once.

val read_lines_l : Pervasives.in_channel -> string list

Read all lines into a list

val read_all : Pervasives.in_channel -> string

Read the whole channel into a buffer, then converted into a string

Output
val with_out : ?mode:int -> ?flags:Pervasives.open_flag list -> string -> (Pervasives.out_channel -> 'a) -> 'a

Same as with_in but for an output channel

val with_out_a : ?mode:int -> ?flags:Pervasives.open_flag list -> string -> (Pervasives.out_channel -> 'a) -> 'a

Similar to with_out but with the Open_append and Open_creat flags activated

val write_line : Pervasives.out_channel -> string -> unit

Write the given string on the channel, followed by "\n"

val write_gen : ?sep:string -> Pervasives.out_channel -> string gen -> unit

Write the given strings on the output. If provided, add sep between every two string (but not at the end)

val write_lines : Pervasives.out_channel -> string gen -> unit

Write every string on the output, followed by "\n".

val write_lines_l : Pervasives.out_channel -> string list -> unit

Misc for Generators

val tee : ('a -> unit) list -> 'a gen -> 'a gen

tee funs gen behaves like gen, but each element is given to every function f in funs at the time the element is produced.

File and file names

How to list recursively files in a directory:

# let files = CCIO.File.read_dir ~recurse:true (CCIO.File.make "/tmp");;
# CCIO.write_lines stdout files;;

See File.walk if you also need to list directories:

# let content = CCIO.File.walk (CCIO.File.make "/tmp");;
# CCGen.map CCIO.File.show_walk_item content |> CCIO.write_lines stdout;;
module File : sig ... end