instance method
OptionParser#on_head
(*::String params) ?{ (*untyped) -> untyped } -> self
(::String params, ::Class | ::Array[::String] | ::Hash[::Symbol, untyped] | ::Regexp obj, ?::String desc) ?{ (*untyped) -> untyped } -> self
(::String short_params, ::String long_params, ::Class | ::Array[::String] | ::Hash[::Symbol, untyped] | ::Regexp obj, ?::String desc) ?{ (*untyped) -> untyped } -> self
(*::String params, ::Proc | ::Method handler) -> self
(::String params, ::Class | ::Array[::String] | ::Hash[::Symbol, untyped] | ::Regexp obj, ?::String desc, ::Proc | ::Method handler) -> self
(::String short_params, ::String long_params, ::Class | ::Array[::String] | ::Hash[::Symbol, untyped] | ::Regexp obj, ?::String desc, ::Proc | ::Method handler) -> self
on_head(*params, &block)
lib/optparse.rb
View on GitHub ↗
# File tmp/rubies/ruby-4.0.0/lib/optparse.rb, line 1664
def on_head(*opts, &block)
define_head(*opts, &block)
self
end
Creates an option from the given parameters params. See Parameters for New Options.
The block, if given, is the handler for the created option. When the option is encountered during command-line parsing, the block is called with the argument given for the option, if any. See Option Handlers.
The new option is added at the head of the summary.