ruby - How method name converts into symbol? -


i try understand ruby, , it's not clear me, how ruby converts name of method symbol?

in method definition give name meth

module mod   def meth     puts 'm'   end end

but if want check if method exists, pass symbol :meth parameter method_defined

mod.method_defined?(:meth) => true

please, me understand, how work?

it's not clear me, how ruby converts name of method :symbol?

that's way method#name works, returns name of method symbol:

m = "foo".method(:size)     #=> #<method: string#size> m.name                      #=> :size m.call                      #=> 3

all methods referencing other methods work way. example, object#methods returns array of method names:

"foo".methods #=> [:<=>, :==, :===, :eql?, :hash, :casecmp, :+, :*, ...]

in method definition give name meth ... if want check, method exist, give method_defined symbol :meth

meth reference variable or method, whereas :meth symbol:

meth = :foo mod.method_defined? meth   #=> false, equivalent mod.method_defined? :foo mod.method_defined? :meth  #=> true

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