Module Command.Flag

Command-line flag specifications.

type 'a t
val required : 'a Arg_type.t -> 'a t

Required flags must be passed exactly once.

val optional : 'a Arg_type.t -> 'a Base.Option.t t

Optional flags may be passed at most once.

val optional_with_default : 'a -> 'a Arg_type.t -> 'a t

optional_with_default flags may be passed at most once, and default to a given value.

val listed : 'a Arg_type.t -> 'a Base.List.t t

listed flags may be passed zero or more times.

val one_or_more : 'a Arg_type.t -> ('a * 'a Base.List.t) t

one_or_more flags must be passed one or more times.

val no_arg : Base.Bool.t t

no_arg flags may be passed at most once. The boolean returned is true iff the flag is passed on the command line.

val no_arg_register : key:'a Univ_map.With_default.Key.t -> value:'a -> Base.Bool.t t

no_arg_register ~key ~value is like no_arg, but associates value with key in the autocomplete environment.

val no_arg_some : 'a -> 'a Base.Option.t t

no_arg_some value is like no_arg, but will return Some value if the flag is passed on the command line, and return None otherwise.

val no_arg_abort : exit:(Base.Unit.t -> Nothing.t) -> Base.Unit.t t

no_arg_abort ~exit is like no_arg, but aborts command-line parsing by calling exit. This flag type is useful for "help"-style flags that just print something and exit.

escape flags may be passed at most once. They cause the command line parser to abort and pass through all remaining command line arguments as the value of the flag.

A standard choice of flag name to use with escape is "--".

val map_flag : 'a t -> f:('a -> 'b) -> 'b t

map_flag flag ~f transforms the parsed result of flag by applying f.