What Do Underscores Before Object Names Mean in Python?

Unveiling the Mystery of Object Name Underscores in Python

When glancing at Python code, one may encounter mysterious underscores preceding object names. Understanding their significance is crucial for deciphering code intent and maintaining code integrity.

Single Underscore: Internal Usage Indication

Within a class definition, a single leading underscore before an attribute or method name hints that it's intended for internal use within that class. This convention implies that other programmers should refrain from accessing it from outside. However, Python does not enforce this privacy restriction.

For module functions, a single underscore preceding the name suggests that it should not be imported from other modules.

Double Underscore: Name Mangling for Privacy

A double leading underscore in front of an identifier invokes a technique known as "name mangling." This process transforms the identifier into a mangled version comprised of the current class name with leading underscores stripped off, followed by two underscores and the original identifier.

This name mangling is employed to establish class-private instance variables, methods, or globals. It serves as a safeguard against accidental access or modification of these protected elements by external code.

Caveat: Limited Privacy

It's important to note that name mangling does not guarantee absolute privacy. Determined individuals may still find ways to access or alter supposedly private variables using techniques like introspection or direct attribute modification.

The above is the detailed content of What Do Underscores Before Object Names Mean in Python?. For more information, please follow other related articles on the PHP Chinese website!