#!/usr/bin/python3
# -*- coding: utf-8 -*-
"""
In a Python program, there are four types of namespaces:
    Built-In
    Global
    Enclosing (definition, not call)
    Local
"""

# Built-ins (some of these commands work differently,
# run interactively versus in a debugger,
# or other python interpreters like ipython.
print(__builtins__)
print(type(__builtins__))
print(dir(__builtins__))

# Works interactively:
# __builtins__.print("hey")

# in script form:
__builtins__["print"]("hey")

# Global
x1 = "global"


def f1() -> None:
    print(x1)

    def g1() -> None:
        print(x1)

    g1()


f1()

# Enclosing
x2 = "global"


def f2() -> None:
    print("print(x2) produces error if here, even though there is a global x2.")
    x2 = "enclosing"
    print(x2)

    def g2() -> None:
        print(x2)

    g2()


f2()

# Local
x3 = "global"


def f3() -> None:
    print("print(x3) produces error if here, even though there is a global x.")
    x3 = "enclosing"
    print(x3)

    def g3() -> None:
        print("print(x3) produces error if here, even though there is an enclosing x3.")
        print("print(x3) produces error if here, even though there is a global x3.")
        x3 = "local"
        print(x3)

    g3()


f3()