First you need to install
gem install pry-doc
Then you can get documentation with the show-doc [method] command (aliased to ? [method])
pry> x = 'potato'
=> "potato"
pry> show-doc x.strip
From: string.c (C Method):
Owner: String
Visibility: public
Signature: strip()
Number of lines: 4
Returns a copy of str with leading and trailing whitespace removed.
" hello ".strip #=> "hello"
"\tgoodbye\r\n".strip #=> "goodbye"
You can even look at the source code with the show-source [method] command (aliased to $ [method])
pry> show-source x.strip
From: string.c (C Method):
Owner: String
Visibility: public
Number of lines: 7
static VALUE
rb_str_strip(VALUE str)
{
str = rb_str_dup(str);
rb_str_strip_bang(str);
return str;
}
This example shows C source, but it will show you the actual Ruby source if there is any. Consider this simple class:
pry> class Foo
pry* def bar
pry* puts 'hello'
pry* end
pry* end
=> nil
You can look at the whole class:
pry> show-source Foo
From: (pry) @ line 2:
Class name: Foo
Number of lines: 5
class Foo
def bar
puts 'hello'
end
end
But also at just a specific method:
pry> show-source Foo#bar
From: (pry) @ line 3:
Owner: Foo
Visibility: public
Number of lines: 3
def bar
puts 'hello'
end
As @banister suggested, you may add custom commands via Pry.commands.command. This way you can define your ? and ?? commands like this in your ~/.pryrc:
Pry.commands.command /(.+) \?\z/ do |a|
run "show-doc", a
end
Pry.commands.command /(.+) \?\?\z/ do |a|
run "show-source", a
end
Note that we need a space between the method and the ?, because Ruby methods may end in ? (e.g. Fixnum#zero?) and those methods would break. Some examples:
pry> puts ?
From: io.c (C Method):
Owner: Kernel
Visibility: private
Signature: puts(*arg1)
Number of lines: 3
Equivalent to
$stdout.puts(obj, ...)
pry> puts ??
From: io.c (C Method):
Owner: Kernel
Visibility: private
Number of lines: 8
static VALUE
rb_f_puts(int argc, VALUE *argv, VALUE recv)
{
if (recv == rb_stdout) {
return rb_io_puts(argc, argv, recv);
}
return rb_funcall2(rb_stdout, rb_intern("puts"), argc, argv);
}
pry> 0.zero? # still works!
=> true
pry> 0.zero? ?
From: numeric.c (C Method):
Owner: Fixnum
Visibility: public
Signature: zero?()
Number of lines: 1
Returns true if fix is zero.
