In IRB, can I view the source of a method I defined earlier?
If I define a method in IRB, is there any way to review its source later in the session?
> def my_method
> puts "hi"
> end
Several screens of output later I'd开发者_StackOverflow社区 like to be able to write something like
> source my_method
and get back:
=> def my_method; puts "hi"; end;
Is this possible?
Not in IRB but in Pry this feature is built-in.
Behold:
pry(main)> def hello
pry(main)* puts "hello my friend, it's a strange world we live in"
pry(main)* puts "yes! the rich give their mistresses tiny, illuminated dying things"
pry(main)* puts "and life is neither sacred, nor noble, nor good"
pry(main)* end
=> nil
pry(main)> show-method hello
From: (pry) @ line 1:
Number of lines: 5
def hello
puts "hello my friend, it's a strange world we live in"
puts "yes! the rich give their mistresses tiny, illuminated dying things"
puts "and life is neither sacred, nor noble, nor good"
end
pry(main)>
Try pry. There is a railscast about it (released this same week!) and it shows you how to show the code by using show-method
.
If you use Ruby 1.9.2 and a newer version of the sourcify gem than available on Rubygems.org (e.g. build the source from GitHub), you can do this:
>> require 'sourcify'
=> true
>>
.. class MyMath
.. def self.sum(x, y)
.. x + y # (blah)
.. end
.. end
=> nil
>>
.. MyMath.method(:sum).to_source
=> "def sum(x, y)\n (x + y)\nend"
>> MyMath.method(:sum).to_raw_source
=> "def sum(x, y)\n x + y # (blah)\n end"
Edit: also check out method_source, which is what pry uses internally.
What I use is method_source I have method code which is basically my wrapper for this gem. Add method_source in Gemfile for Rails apps. And create initializer with following code.
# Takes instance/class, method and displays source code and comments
def code(ints_or_clazz, method)
method = method.to_sym
clazz = ints_or_clazz.is_a?(Class) ? ints_or_clazz : ints_or_clazz.class
puts "** Comments: "
clazz.instance_method(method).comment.display
puts "** Source:"
clazz.instance_method(method).source.display
end
Usage is:
code Foo, :bar
or with instance
code foo_instance, :bar
Better approach is to have class with in /lib folder with your irb extension, than you just require it in one of initializers (or create your own)
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