Symbol Table in Python

Question

How can we see the Symbol-Table of a python source code?

I mean, Python makes a symbol table for each program before actually running it. So my question is how can I get that symbol-table as output?

Answer 1

If you are asking about the symbol table that is used when generating bytecode, take a look at the symtable module. Also, these two articles by Eli Bendersky are fascinating, and very detailed:

Python Internals: Symbol tables, part 1

Python Internals: Symbol tables, part 2

In part 2, he details a function that can print out a description of a symtable, but it seems to have been written for Python 3. Here's a version for Python 2.x:

def describe_symtable(st, recursive=True, indent=0):
    def print_d(s, *args):
            prefix = ' ' *indent
            print prefix + s + ' ' + ' '.join(args)

    print_d('Symtable: type=%s, id=%s, name=%s' % (
            st.get_type(), st.get_id(), st.get_name()))
    print_d('  nested:', str(st.is_nested()))
    print_d('  has children:', str(st.has_children()))
    print_d('  identifiers:', str(list(st.get_identifiers())))

    if recursive:
            for child_st in st.get_children():
                    describe_symtable(child_st, recursive, indent + 5)