Introducing the optparse-simple gem

Tuesday, 11 May 2010 10:32

The optparse-simple gem uses a Polyrex document to fetch, and validate command-line arguments into a simple hash.

*installation*


sudo gem1.9.1 install optparse-simple



Successfully installed optparse-simple-0.2.0

1 gem installed

Installing ri documentation for optparse-simple-0.2.0...

Updating class cache with 3148 classes...

Installing RDoc documentation for optparse-simple-0.2.0...

Polyrex schema: options/option[name,switch,alias,value,mandatory]/error[msg]

*example*



require 'optparse-simple'

args = %w(-s --list=45 refresh filename filexx3)

h = OptParseSimple.new('/home/james/learning/ruby/optionsx.xml', args).to_h

#=> {:list=>"45", :sort=>nil, :refresh=>nil, :file1=>"filename", :file2=>"filexx3"}

file: optionsx.xml

Note: The error messages within each option are positioned by priority (mandatory being 1st, followed by value).

Resources:
- jrobertson's optparse-simple at master [github.com]
- Using OptParseSimple [dzone.com]

*update: 11-May-2010 @ 5:23pm*
To catch errors use the RuntimeError case e.g.



require 'optparse-simple'



begin

  args = %w(-s --list=45 refresh filename filexx3 dhgf)

  h = OptParseSimple.new('/home/james/learning/ruby/optionsx.xml', args).to_h

rescue RuntimeError => myStandardError

	puts myStandardError

end

#=> invalid option: dhgf not recognised

see Handle exceptions in Ruby [dzone.com]