Intercept function call

["Fabrício de Alexandria" <fabricio@...>]

Here is my situation. Suppose that I have three functions:

function x()
  print "x"
end

function y()
  print "y"
end

function z()
  print "z"
end

x()
y()


I want to execute x() and y() but before or after the execution of x() I
want to execute z(). Something like during the execution of the program I
want to intercept the x() function call, execute z() and then return to
the normal execution of the program. How can I do that?

I searched something like this in the archive but I didn't find anything.




Fabrício de Alexandria Fernandes
HomePage: http://www.ppgsc.ufrn.br/~fabricio
E-mail: fabricio@ppgsc.ufrn.br
UFRN - CCET - DIMAp
Natal - RN - Brasil