ruby - What is the difference between a method and a proc object? -

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i know methods in ruby not objects procs , lambdas are. there difference between them other that? because both can pass around. makes proc objects different method?

method:

1.8.7-p334 :017 > def a_method(a,b) 1.8.7-p334 :018?>   puts "a method args: #{a}, #{b}" 1.8.7-p334 :019?>   end 1.8.7-p334 :021 > meth_ref = object.method("a_method")  => #<method: class(object)#a_method>  1.8.7-p334 :022 > meth_ref.call(2,3)

proc object:

  = lambda {|a, b| puts "#{a}, #{b}"}   a.call(2,3)

you said in question "methods not objects" have careful distinguish between "method" , "method".

a "method" defined set of expressions given name , put method table of particular class easy lookup , execution later.

a "method" object (or "unboundmethod" object) actual ruby object created calling method / instance_method / etc. , passing name of "method" argument.

you may find useful read rdoc documentation unboundmethod, method, , proc. rdoc pages list different instance methods available each type.

basically, method object "bound" object self points object when call method, , proc doesn't have behavior; self depends on context in proc created/called.


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