clap/examples/escaped-positional-derive.md

This requires enabling the [derive feature flag][crate::_features].

You can use -- to escape further arguments.

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

$ escaped-positional-derive --help
A simple to use, efficient, and full-featured Command Line Argument Parser

Usage:
    escaped-positional-derive[EXE] [OPTIONS] [-- <SLOP>...]

Arguments:
    [SLOP]...    

Options:
    -f               
    -p <PEAR>        
    -h, --help       Print help information
    -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"]