Can you translate this debugging macro from C++ to python?

Question

I use this very helpful macro when developing in C++:

#define DD(a) std::cout << #a \" = [ \" << a << \" ]\" << std::endl;std::cout.f         


        

Answer 1

As @Andrea Spadaccini and @adirau point out, it is not possible to reliably map values back to Python variable names. You could trawl through all namespaces looking for some variable name that references the given value, but that would be fighting the system and liable to return the wrong variable name.

Much easier it is to just pass the variable name:

import inspect
def pv(name):
    frame,filename,line_number,function_name,lines,index=inspect.getouterframes(
        inspect.currentframe())[1]    
    # print(frame,filename,line_number,function_name,lines,index)
    val=eval(name,frame.f_globals,frame.f_locals)
    print('{0}: {1}'.format(name, val))


a=5
pv('a')

yields:

a: 5