Icod.Argh 1.1.0

Icod.Argh

Icod.Argh is a command-line arguments handler and processor.

Usage

To process the System.String[] args, one first defines which switches one supports via instances of the Definition class, and passes them to the Processor class and invokes the Parse method.

Definition

The Definition class is used to define a switch, and what possible forms it can take on the command line. For example, it is quite common for "help" to be supported by both "-h" or "--help". Icod.Argh permits one definition for any given switch not matter how many forms it make take. Example:

var help = Icod.Argh.Definition( "help", new System.String[] { "-h", "--help", "/help" } );

Processor

The Processor performs the work of analyzing and parsing out the args based on the supplied Definition list. Once the args have been parsed, the Processor instance can be queried to see which switches were present, if they have associated values, and so forth. Example:

private static System.Int32 main( System.String[] args ) {
	var processor = new Icod.Argh.Processor(
		new Icod.Argh.Definition[] {
			// help and copyright unary flags which perform respective display and then exit
			// (ex: --help), (ex: --copyright)
			new Icod.Argh.Definition( "help", new System.String[] { "-h", "--help", "/help" } ),
			new Icod.Argh.Definition( "copyright", new System.String[] { "-c", "--copyright", "/copyright" } ),

			// input is optional, but if present must precede a file pathname (ex: --input C:\foo\bar.baz)
			new Icod.Argh.Definition( "input", new System.String[] { "-i", "--input", "/input" } ),

			// suffix is required and must precede a string (ex: --suffix "this string has spaces")
			new Icod.Argh.Definition( "suffix", new System.String[] { "-s", "--suffix", "/suffix" } ),

			// trim is a unary flag, used on its own (ex: --trim)
			new Icod.Argh.Definition( "trim", new System.String[] { "-t", "--trim", "/trim" } ),
		},
		System.StringComparer.OrdinalIgnoreCase
	);
	processor.Parse( args );

	if ( processor.Contains( "help" ) ) {
		PrintUsage();
		return 1;
	} else if ( processor.Contains( "copyright" ) ) {
		PrintCopyright();
		return 1;
	}

	System.Func<System.String, System.Collections.Generic.IEnumerable<System.String>> reader;
	// input is optional
	if ( processor.TryGetValue( "input", true, out var inputPathName ) ) {
		// if present it must specify a file pathname
		if ( System.String.IsNullOrEmpty( inputPathName ) ) {
			PrintUsage();
			return 1;
		} else {
			reader = x => ReadFile( x );
		}
	} else {
		// if not specified, then we read from StdIn
		reader = x => ReadStdIn();
	}

	if ( 
		( !processor.TryGetValue( "suffix", true, out var suffix ) )
		|| System.String.IsNullOrEmpty( suffix )
	) {
		PrintUsage();
		return 1;
	}

	System.Boolean trim = processor.Contains( "trim" );

	// do work

	return 0;
}

Copyright and Licensing

Icod.Argh is a command-line arguments handler and processor. Copyright (C) 2023 Timothy J. Bruce

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA