Has a method been called?

Ruby
1

Hi,
Is it possible to find out if a method has been called except by adding
a flag to it?

class Whatever
@flag = 0

def method_called
@flag += 1
end

def has_method_been_called
false
return true if @flag > 0
end

end

Cheers

Aidy

2

On 07/09/06, aidy [email protected] wrote:

Have a look at set_trace_func. It’s documented in the pickaxe book
online at http://www.rubycentral.com/book/ospace.html (just scroll
down to Tracing Your Program’s Execution). You’ll probably be
interested in the ‘call’ events.

Farrel

3

On 9/7/06, aidy [email protected] wrote:

def has_method_been_called
false
return true if @flag > 0
end

end

Cheers

Aidy

If it’s enough for you to know that off-line, you can use rcov or
ruby-prof for that. Run rcov and see whether it’s code was visited. If
you need to know in the runtime, that’s another story :wink:

4

On 9/7/06, Jan S. [email protected] wrote:

end
Aidy

If it’s enough for you to know that off-line, you can use rcov or
ruby-prof for that. Run rcov and see whether it’s code was visited. If
you need to know in the runtime, that’s another story :wink:

You can also whip up a little meta programming mess (warning thrown
together, collision causing, not thread safe code follows):

class Module

def flag_use(sym)
self.instance_eval do
define_method “#{sym}_called?” do
false
end

  flag_name = "use_flagged_#{sym}".to_sym
  alias_method flag_name, sym
  define_method sym do
    self.class.instance_eval do
      alias_method sym, flag_name
      define_method "#{sym}_called?" do
        true
      end
    end
    flag_name
  end
end

end
end

Then…

class Foo
def bar
puts :bar
end
flag_use :bar
end

f = Foo.new
p f.bar_called?
f.bar
p f.bar_called?

pth

5

On Fri, Sep 08, 2006 at 12:23:10AM +0900, Jan S. wrote:

return true if @flag > 0
end

end

If it’s enough for you to know that off-line, you can use rcov or
ruby-prof for that. Run rcov and see whether it’s code was visited. If
you need to know in the runtime, that’s another story :wink:

You can do it with rcov’s API:

RUBY_VERSION # => “1.8.5”
require ‘rcov’
class Foo;
def foo; 1 end
def bar; 1 end
end

analyzer = Rcov::CallSiteAnalyzer.new
analyzer.run_hooked do
f = Foo.new
f.foo
end

def analyzer.executed?(selector); !!defsite(selector) end

analyzer.executed? “Foo#foo” # => true
analyzer.executed? “Foo#bar” # => false

However, in this case I’d rather intercept the method call, record it
and
redispatch (standard alias_method/module_eval idiom, or define_method if
the
redefined methods take no blocks or you’re using Ruby 1.9).