ri_for

The ri_for gem allows "runtime documentation lookup", it show a method's source code/comments, ri (if available), arity, parameters, etc. all at runtime (for example within an irb session).

Don't know what a method does? Look it up! It has proven quite useful, and I wouldn't do a ruby-debug session without it--you might like it.

Examples:

File.ri_for :delete

sig: File.delete arity -1 appears to be a c method Searching ri for sig: File.delete arity -1 ... ----------------------------------------------------------- File::delete File.delete(file_name, ...) => integer File.unlink(file_name, ...) => integer

---

 Deletes the named files, returning the number of names passed as
 arguments. Raises an exception on any error. See also +Dir::rmdir+.

(end ri) => "sig: File.delete arity -1"

(or alternatively use >> File.method(:delete).ri_for)

or, given this dynamically generated class, it can still show runtime parameter information:

class A; def go(a); end; end

A.new.ri_for :go

sig: A#go arity 1 def go(a)

do nothing

end Parameters: go(a) Searching ri for sig: A#go arity 1 ... Nothing known about A (end ri) => "Parameters: go(a)"

Or (my favorite) use it within debug session:

74 assert(true == false)

(rdb:1) ri_for :assert #<Method: StoreControllerTest(Test::Unit::Assertions)#assert> arity: -2 ri for Test::Unit::Assertions#assert ------------------------------------------ Test::Unit::Assertions#assert assert(boolean, message=nil)

 From gem test-unit-2.0.1

---

 Asserts that +boolean+ is not false or nil.

 Example:

   assert [1, 2].include?(5)

(end ri) def assert(boolean, message = nil) _wrap_assertion do assert_block("assert should not be called with a block.") do (not block_given?) end assert_block(build_message(message, "<?> is not true.", boolean)) { boolean } end end Parameters: assert(boolean, message = nil)

Thus, you can look at methods' source/rdocs without having to run the methods and step into them. Deftly convenient.

=========Installation=====

$ gem install ri_for

Usage:

require 'ri_for' ClassName.ri_for :method_name # class or instance method name

some_instance.ri_for :method_name

Other goodies included:

Object#my_methods (stolen from a website somewhere)

An example:

class A; def go; end; end A.new.my_methods => {:first, :second, :third]}

Object#methods2 (like #methods, but inserts a marker after my_methods are shown)

A.new.methods2 => ["go", :"inherited methods after this point >>", "to_yaml_style", "inspect", "methods_old", "clone", "public_methods", "display", "instance_variable_defined?", "equal?", "freeze", "to_yaml_properties", "methods"...]

=== Attributions ===

This gem wraps for convenience the functionality of Method#source_location, ruby2ruby, et al, and was inspired by a snippet from manvenu, SourceRef (MBARI), and Python's Method#desc. It also wouldn't be useful without irb and the ruby-debug folks. Thanks!

=== Related ===

https://github.com/dadooda/ori (just lists ri, not method bodies and parameters, like mine does). also irb has a "help" command for obtaining (just lists ri) but it's pretty obscure nobody knows about it.

help "Array" help "Array#[]" (just displays ri)

There are quite a few "#methods" helper utilties out there, too.
irbtools also lists a lot of other irb helpers.

=== Feedback ===

Comments/suggestions welcome rogerdpack on gmail or rdp on github

github.com/rdp/ri_for