Module Arg

module Arg = struct ... end

Types

spec

`=`	`Unit`	of `(unit -> unit)` Call the function with unit argument
`\|`	`Set`	of `bool Pervasives.ref` Set the reference to true
`\|`	`Clear`	of `bool Pervasives.ref` Set the reference to false
`\|`	`String`	of `(string -> unit)` Call the function with a string argument
`\|`	`Int`	of `(int -> unit)` Call the function with an int argument
`\|`	`Float`	of `(float -> unit)` Call the function with a float argument
`\|`	`Rest`	of `(string -> unit)` Stop interpreting keywords and call the function with each remaining argument

Exceptions
`Bad`	of `string` Functions in `spec` or `anonfun` can raise `Arg.Bad` with an error message to reject invalid arguments.

Simple values
`current`	`int Pervasives.ref` Position (in `Sys.argv`) of the argument being processed. You can change this value, e.g. to force `Arg.parse` to skip some arguments.

Functions


parse

: keywords:(string * spec * string) list -> others:(string -> unit) -> errmsg:string -> unit

Arg.parse speclist anonfun usage_msg parses the command line. speclist is a list of triples (key, spec, doc). key is the option keyword, it must start with a '-' character. spec gives the option type and the function to call when this option is found on the command line. doc is a one-line description of this option. anonfun is called on anonymous arguments. The functions in spec and anonfun are called in the same order as their arguments appear on the command line.
If an error occurs, Arg.parse exits the program, after printing an error message as follows:

The reason for the error: unknown option, invalid or missing argument, etc.
usage_msg
The list of options, each followed by the corresponding doc string.

For the user to be able to specify anonymous arguments starting with a -, include for example ("-", String anonfun, doc) in speclist.
By default, parse recognizes a unit option -help, which will display usage_msg and the list of options, and exit the program. You can override this behaviour by specifying your own -help option in speclist.


usage

: keywords:(string * spec * string) list -> errmsg:string -> unit

Arg.usage speclist usage_msg prints an error message including the list of valid options. This is the same message that Arg.parse prints in case of error. speclist and usage_msg are the same as for Arg.parse.