Current method

ruby-talk
1

How could I know which method (if any) is currently being executed? E.g.

class Foo
   def bar
      self.inspect
   end
end

Tells me which class I'm in, but not which method. How would I go
about doing that? Cheers
   -CWS

2

Claus Spitzer wrote:

How could I know which method (if any) is currently being executed? E.g.

class Foo
   def bar
      self.inspect
   end
end

Tells me which class I'm in, but not which method. How would I go
about doing that? Cheers

Here is an example based on something I believe Rick Kilmer posted here some time ago, plus some additional neat Ruby magic for dynamic code tracing (also from Rich, I think, but I might be wrong on that).

# Eval a code block using the original context of the variables
def trace( &block )
   expr = block.call
   puts "trace: #{expr} = #{eval(expr, block)}"
end

# Get the name of the immediate caller
def my_name_is
   caller[0].split( /:in /).last.gsub( /[\'|\`]/, '' )
end

# An example method to demo the previous two helper methods
def something( z )
   puts "My name is \"#{my_name_is}\""
   x = 5
   y = 7
   trace { "x + y + z" } # Show this to Java(tm) fans.
end

# Simple method to demo nested calls to my_name_is
# Not quite unit testing, I know ...
def foo
   puts "My name is \"#{my_name_is}\""
   something( 12 )
end

something 10
foo

James

3

Hmm. So there is no built-in way of doing this? What about lambdas?
Should the result be nil, or stay silent?

irb(main):001:0> def my_name_is
irb(main):002:1> caller[0].split( /:in /).last.gsub( /[\'|\`]/, '' )
irb(main):003:1> end
=> nil
irb(main):004:0> 1.upto(3){ |i|
irb(main):005:1* p i
irb(main):006:1> my_name_is
irb(main):007:1> }
1
2
3
=> 1
irb(main):008:0>

even more interesting is

irb(main):011:0> 1.upto(3){ |i|
irb(main):012:1* p i
irb(main):013:1> p my_name_is
irb(main):014:1> }
1
"irb_binding"
2
"irb_binding"
3
"irb_binding"
=> 1
irb(main):015:0>

Cheers!
   -CWS

···

On Mon, 19 Jul 2004 04:28:10 +0900, James Britt <jamesunderbarb@neurogami.com> wrote:

Here is an example based on something I believe Rick Kilmer posted here
some time ago, plus some additional neat Ruby magic for dynamic code
tracing (also from Rich, I think, but I might be wrong on that).

# Eval a code block using the original context of the variables
def trace( &block )
   expr = block.call
   puts "trace: #{expr} = #{eval(expr, block)}"
end

# Get the name of the immediate caller
def my_name_is
   caller[0].split( /:in /).last.gsub( /[\'|\`]/, '' )
end

# An example method to demo the previous two helper methods
def something( z )
   puts "My name is \"#{my_name_is}\""
   x = 5
   y = 7
   trace { "x + y + z" } # Show this to Java(tm) fans.
end

# Simple method to demo nested calls to my_name_is
# Not quite unit testing, I know ...
def foo
   puts "My name is \"#{my_name_is}\""
   something( 12 )
end

something 10
foo

James

4

James Britt wrote:

Here is an example based on something I believe Rick Kilmer posted here some time ago, plus some additional neat Ruby magic for dynamic code tracing (also from Rich, I think, but I might be wrong on that).

# Eval a code block using the original context of the variables
def trace( &block )
  expr = block.call
  puts "trace: #{expr} = #{eval(expr, block)}"
end
  trace { "x + y + z" } # Show this to Java(tm) fans.

Using Binding.of_caller (available from http://noegnud.sourceforge.net/flgr/binding_of_caller.rb\) this can be simplified to trace "x + y + z":

require 'binding_of_caller'

def trace(expr)
   Binding.of_caller do |context|
     result = eval(expr, context)
     puts "trace: #{expr} = #{result.inspect}"
     return result
   end
end

I'm using it like this:

irb(main):026:0> x = 2; y = 3; trace "(x + y) ** (x * y)"
trace: (x + y) ** (x * y) = 15625
=> 15625

Regards,
Florian Gross