Funarg problem
（重定向自Funarg）
In computer science, the funarg problem refers to the difficulty in implementing first-class functions (functions as first-class objects) in programming language implementations so as to use stack-based memory allocation of the functions.
The difficulty only arises if the body of a nested function refers directly (i.e., not via argument passing) to identifiers defined in the environment in which the function is defined, but not in the environment of the function call. To summarize the discussion below, two standard resolutions are to either forbid such references or to create closures.