These are cases which could be detected by clap
, and potentially warn at compile time. Maybe even with a nice web URL to more info.
First, a little about the syntax to understand the setup of rule. This syntax will make each rule more concise so we don't have to write an entire clap
definition.
--opt
is an option--flag
is a flag#
(i.e. 1
or 2
) is a positional argumentval
is an option valueCan be used on val
or Arg types
*
: zero or more+
: one or more?
: zero or one{#,#}
: # to # times (i.e. {1,4}
is one to four times)<>
: required=
: requires equals,
: requires delimiter(foo,bar)
: values can only be foo
or bar
$ prog --opt foo # is foo option val or positional?
$ prog 1 --opt $ prog --opt -- 1
--opt
$ prog --opt foo # foo is positional $ prog --opt=val foo
$ prog --opt foo bar # is bar option val or positional?
$ prog 1 --opt val $ prog --opt val -- 1
--opt
only one val per occurrence$ prog --opt foo bar # bar is positional $ prog --opt val bar --opt foo # bar is positional