Flag: Event Handlers

Event Handlers associated with a flag

The standard events and its handlers are:

• .OnParseValue(...OnParseValueHandler)
• .OnMatched(...OnMatchedHandler)
• .OnChanging(...OnChangingHandler)
• .OnChanged(...OnChangedHandler)
• .OnSet(...OnSetHandler)

All of these handlers are specific for each phrases in cmdr runner working: a subcommand will be parsed (OnParseValue), parsed ok (OnMatched), a flag parsed (OnMatched) and the raw string are been parsed as its value (OnChanging), and the new value accepted (OnChanged), or a store entry value was been changed programmatically (OnSet).

The differences of OnSet and OnChanged is, the first one will be called while cmd.Store().Set("some.key", newval) ran, it means a programmatic modification. And the last one will be called while cmdr is parsing the command-line arguments.

cmdr-loaders works with cmdr main library, and assumes its loading action is OnLoading(cb) wrapped. So in the time the OnSet won't be triggered.

After loaded, any modifications are recorded, that would be a changeset. The modifications will be written back to a Alternative config file at terminating app. The Write-back feature can be descibed at Here.

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