Fredrik Lundh wrote: > (I'm afraid I don't really understand the point of your examples; what > is it you're really trying to do here ?)
A function is passed a bunch of string expressions like, x = "a+b" y= "x*a" z= "x+y" where a and b are assumed to have been assigned values in the local namespace. Now I have to evaluate another string such as, "z+y+x" So as you say, I could do: x=eval(x), y=eval(y), z=eval(z) and finally eval("z+y+x") but the problem is that the initial strings are in no particular order, so I don't know the sequence in which to perform the first 3 evaluations. I was wondering if there was a simple way to 'pattern-match' so that the required substitutions like z->x+y->x+x*a->(a+b)+(a+b)*a could be done automatically. I apologise if this is still not quite clear. Abhishek -- http://mail.python.org/mailman/listinfo/python-list