Non-standard: This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.
Deprecated: This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.
Note: In strict mode, accessing caller
of a function throws an error — the API is removed with no replacement. This is to prevent code from being able to "walk the stack", which both poses security risks and severely limits the possibility of optimizations like inlining and tail-call optimization. For more explanation, you can read the rationale for the deprecation of arguments.callee
.
The caller
accessor property of Function
instances returns the function that invoked this function. For strict, arrow, async, and generator functions, accessing the caller
property throws a TypeError
.