clap/examples/escaped_positional_derive.md

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You can use -- to escape further arguments.

Let's see what this looks like in the help:

$ escaped_positional_derive --help
clap [..]

A simple to use, efficient, and full-featured Command Line Argument Parser

USAGE:
    escaped_positional_derive[EXE] [OPTIONS] [-- <SLOP>...]

ARGS:
    <SLOP>...    

OPTIONS:
    -f               
    -h, --help       Print help information
    -p <PEAR>        
    -V, --version    Print version information

Here is a baseline without any arguments:

$ escaped_positional_derive
-f used: false
-p's value: None
'slops' values: []

Notice that we can't pass positional arguments before --:

$ escaped_positional_derive foo bar
? failed
error: Found argument 'foo' which wasn't expected, or isn't valid in this context

USAGE:
    escaped_positional_derive[EXE] [OPTIONS] [-- <SLOP>...]

For more information try --help

But you can after:

$ escaped_positional_derive -f -p=bob -- sloppy slop slop
-f used: true
-p's value: Some("bob")
'slops' values: ["sloppy", "slop", "slop"]

As mentioned, the parser will directly pass everything through:

$ escaped_positional_derive -- -f -p=bob sloppy slop slop
-f used: false
-p's value: None
'slops' values: ["-f", "-p=bob", "sloppy", "slop", "slop"]