Namespaces

A namespace in computer science is essentially a container where identifiers (names of types, variables, functions, etc.) live. It allows different developers, libraries, or parts of a program to use the same identifier names without causing conflicts, because the same identifier can be bound to different entities in different namespaces.

In other words, namespaces provide a way to disambiguate identifiers that might be common and likely to be used more than once. This way, even if the same identifier is used in different parts of a program, as long as they are in different namespaces, they are considered to be different entities.

Example

In Python Index, namespaces are implemented as dictionaries that map names to objects, and they have different lifetimes depending on where they are declared. For example, a local namespace in a function is created when the function is called and deleted when the function returns; a module’s namespace lasts as long as the module is in memory; and the built-in namespace that contains Python’s built-in functions exists for the life of the program.

# In the global namespace
x = 10
 
def my_func():
    # In the local namespace of my_func
    x = 20
    print(x)  # Prints: 20
 
my_func()
print(x)  # Prints: 10