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docs (old -- 1.4)

Optik Documentation (version 1.5)

philosophy and background; if you're not sure what the difference between an argument and an option is, start here
introduction to Optik; covers what you need to know to get started
concise, detailed reference that covers all of Optik's everyday features
how to call custom code when an option is seen on the command-line
why and how to extend Optik (eg. how to add new actions and types)