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docs (current -- 1.5)

Optik Documentation (version 1.4)

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
option callbacks: 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)