clap/examples/escaped-positional.md
Ed Page 162a556dba fix(error): Try to soften unexpected argument/value errors
Adding "found" might seem minor but I feel it has a slight softening on the message.  It also maintains scanability as it is at the end and short.

As this is a one-off message change and not a styling issue to be consistent with, I think this is safe to put in a patch release.
2023-01-13 21:29:49 -06:00

1.2 KiB

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

You can use -- to escape further arguments.

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

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

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

Arguments:
  [SLOP]...  

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

Here is a baseline without any arguments:

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

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

$ escaped-positional foo bar
? failed
error: unexpected argument 'foo' found

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

For more information, try '--help'.

But you can after:

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