execfilefilename

execfilefilename is a term used to describe a programming operation in which the contents of a file are read and executed as code, using the file’s name as the source of the code. In practice, it denotes a function, command, or pattern that takes a filename as input and runs the code contained in that file within the current program’s context or in a provided execution namespace.

The concept has historical ties to languages that supported dynamic code execution from files. For example, in Python 2 there was a built-in function called execfile that read and executed a file’s contents in the current global namespace. In Python 3, this specific function was removed, and similar behavior is achieved by reading the file and passing its contents to the exec function, or by using importlib for module-like loading. Other languages offer analogous capabilities through include, require, or dynamic import mechanisms, which differ in scope, namespace, and error handling.

Typical behavior of an execfilefilename operation includes reading the file, optionally compiling it, and executing the resulting code. The execution can occur in the caller’s global and local namespaces or within a user-supplied namespace mapping. Language and environment determine whether side effects are visible outside the executed code, and whether security checks or sandboxing are available.

Security and reliability considerations are central. Executing code from a file can run arbitrary instructions, access resources, or alter program state. It should be avoided for untrusted sources, and when used, should be restricted with permissions, sandboxes, or safer alternatives such as modular imports or separate processes.

See also: exec, eval, importlib, include, require.