Crate pargs

pargs - command line argument parser

the design goal of pargs is to simply return parsed arguments to a caller in a defined format for ease of lookup.

pargs works with three common types of arguments: commands, flags and options.

Using pargs

using pargs is very simple: define all three types of arguments that your program needs and pass them as individual Vec<String> to pargs::parse(). parse() will return a HashMap of the parsed arguments keyed by category so that your application can easily interpret them.

Definitions

command_args are defined as single arguments that do not have an assigned value command_args args should be entered without a dash flag_args are intended to be boolean values flag_args should not be assigned a value - if they exist, they are interpreted as true option_args should be assigned a value option_args should be denoted with a - character option_args can be assigned a value via = or space between arg and value

Example

The following example shows a simple program that defines all three types of arguments (commands, flag and option). Pargs is passed a Vec<String> from env::args() at which point it parses the arguments and returns them to the program in a HashMap<String, Vec<String>> data structure.

use std::env;

fn main() {
   let actual_args: Vec<String> = env::args().collect();
   let command_args = vec![String::from("cool_command")];
   let flag_args = vec![String::from("-h")];
   let option_args = vec![String::from("-j"), String::from("-i")];

   let parsed_args = pargs::parse(actual_args, command_args, flag_args, option_args);

   match parsed_args {
       Ok(parsed_args) => println!("{:?}", parsed_args),
       Err(parsed_args) => println!("{}", parsed_args),
   }
}

If we run this program with cargo run cool_command -h -j=test123 -i=test456, the output will be {"flag_args": ["-h"], "command_args": ["cool_command"], "option_args": ["-j", "test123", "-i", "test456"]}.

From here, we can lookup the values using HashMap's methods and utilize them in our program.

Functions

parse

parses arguments in relation to expected optional and required arguments