Expand description
Simple getopt alternative.
Construct a vector of options, either by using reqopt
, optopt
, and
optflag
or by building them from components yourself, and pass them to
pgetopts
, along with a vector of actual arguments (not including
argv[0]
). You’ll either get a failure code back, or a match. You’ll have
to verify whether the amount of ‘free’ arguments in the match is what you
expect. Use opt_*
accessors to get argument values out of the matches
object.
Single-character options are expected to appear on the command line with a single preceding dash; multiple-character options are expected to be proceeded by two dashes. Options that expect an argument accept their argument following either a space or an equals sign. Single-character options don’t require the space.
§Usage
This crate is on crates.io and can be
used by adding pgetopts
to the dependencies in your project’s Cargo.toml
.
[dependencies]
pgetopts = "0.2"
and this to your crate root:
extern crate pgetopts;
§Example
The following example shows simple command line parsing for an application
that requires an input file to be specified, accepts an optional output file
name following -o
, and accepts both -h
and --help
as optional flags.
extern crate pgetopts;
use pgetopts::Options;
use std::env;
fn do_work(inp: &str, out: Option<String>) {
println!("{}", inp);
match out {
Some(x) => println!("{}", x),
None => println!("No Output"),
}
}
fn print_usage(program: &str, opts: Options) {
println!("Usage: {} [options]", program);
print!("{}", opts.options());
}
fn main() {
let args: Vec<String> = env::args().collect();
let program = args[0].clone();
let mut opts = Options::new();
opts.optopt("o", "", "set output file name", "NAME");
opts.optflag("h", "help", "print this help menu");
let matches = match opts.parse(&args[1..]) {
Ok(m) => { m }
Err(f) => { panic!(f.to_string()) }
};
if matches.opt_present("h") {
print_usage(&program, opts);
return;
}
let output = matches.opt_str("o");
let input = if !matches.free.is_empty() {
matches.free[0].clone()
} else {
print_usage(&program, opts);
return;
};
do_work(&input, output);
}
Structs§
- The result of checking command line arguments. Contains a vector of matches and a vector of free strings.
- A description of the options that a program can handle
Enums§
- The type returned when the command line does not conform to the expected format. Use the
Debug
implementation to output detailed information. - The type of failure that occurred.
- Describes whether an option has an argument.
- Describes how often an option may occur.
- What parsing style to use when parsing arguments
Type Aliases§
- The result of parsing a command line with a set of options.