ng-clp

Ng-clp (no-grammar definition command-line parser) is one of Rust's command-line parsers. A normal command-line parser generates a parser from the definition of command-line options that accepts a command line according to its grammar. In contrast, ng-clp uses a universal parser to discover what it assumes to be options or arguments from the given command-line arguments.

How it works?

You can run a sample program with cargo run as follows:

$ cargo run -- foo -bar bal --bra boo
Argument: foo
Option: -b ar
Argument: bal
Option: --bra boo

Format of flags and options accepted by ng-clp

The arguments, flags, and options accepted by ng-clp can be described as follows (option names, arguments, etc. are capitalized here to be easier to distinguish).

Format	Parsed
`-A`	Flag `-A`.
`-A BC`	Option `-A` with argument `BC`.
`-ABC`	Option `-A` with argument `BC`.
`--AB`	Flag `--AB`.
`--AB CD`	Option `--AB` with the argument `CD`.
`--AB=CD`	Option `--AB` with argument `CD`.

"But isn't that ambiguous?" If you are wondering, you are correct.

When the command line is:

-a bc

ng-clp allows treating with the command line in the following two interpretations.

A flag -a appears (with no argument; the following bc is a normal command-line argument that has nothing to do with the flag -a).
An option -a appears with argument bc.

How do I use ng-clp?

(1) Add a dependency to ng-clp in Cargo.toml:

[dependencies]
ng-clp = "0.1"

(2) Copy the boilerplate code boilerplate/main.rs in your main.rs and modify it.

License

MIT/Apache-2.0

Links