# Module OptParse.StdOpt

    module StdOpt: sig .. end

This module contains various standard options.

Flag options

    val store_const : ?default:'a -> 'a -> 'a OptParse.Opt.t

`store_const ?default const` returns a flag option which stores the constant value `const` when the option is encountered on the command line.

    val store_true : unit -> bool OptParse.Opt.t

`store_true ()` returns an option which is set to true when it is encountered on the command line. The default value is false.

    val store_false : unit -> bool OptParse.Opt.t

`store_false ()` returns an option which is set to false when it is encountered on the command line. The default value is true.

    val count_option : ?dest:int Stdlib.ref -> ?increment:int -> unit -> int OptParse.Opt.t

Create a counting option which increments its value each time the option is encountered on the command line.

- Returns the newly created option.

`dest` : Reference to the option value. Useful for making options like '--quiet' and '--verbose' sharing a single value.
`increment` : Increment to add to the option value each time the option is encountered.

    val incr_option : ?dest:int Stdlib.ref -> unit -> int OptParse.Opt.t

Exactly identical to `count_option ~dest:dest ~increment:1 ()`.

    val decr_option : ?dest:int Stdlib.ref -> unit -> int OptParse.Opt.t

Exactly identical to `count_option ~dest:dest ~increment:(-1) ()`.

Value options

    val int_option : ?default:int -> ?metavar:string -> unit -> int OptParse.Opt.t

`int_option ?default ?metavar ()` returns an option which takes a single integer argument. If `~default` is given it is the default value returned when the option has not been encountered on the command line.

    val float_option : ?default:float -> ?metavar:string -> unit -> float OptParse.Opt.t

See `OptParse.StdOpt.int_option`.

    val str_option : ?default:string -> ?metavar:string -> unit -> string OptParse.Opt.t

See `OptParse.StdOpt.int_option`.

Callback options

    val int_callback : ?metavar:string -> (int -> unit) -> unit OptParse.Opt.t

`int_callback ?metavar f` returns an option which takes a single integer argument and calls `f` with that argument when encountered on the command line.

    val float_callback : ?metavar:string -> (float -> unit) -> unit OptParse.Opt.t

See `OptParse.StdOpt.int_callback`.

    val str_callback : ?metavar:string -> (string -> unit) -> unit OptParse.Opt.t

See `OptParse.StdOpt.int_callback`.

Special options

    val help_option : unit -> 'a OptParse.Opt.t

`help_option ()` returns the standard help option which displays a usage message and exits the program when encountered on the command line.

    val version_option : (unit -> string) -> 'a OptParse.Opt.t

`version_option f` returns the standard version option which displays the string returned by `f ()` (and nothing else) on standard output and exits.