sandbox()

sandbox(<expression>, <functions>[, <unknown>[, <user functions>[, <allow>]]])

Evaluates <expression> and returns the result, with the functions named in <functions>, a list separated by spaces, refused. A refused function returns #-1 PERMISSION DENIED and does nothing. The refusal covers everything <expression> evaluates, including attributes it calls with u() and functions it calls through #apply.

<unknown>: if 1, a refused function returns #-1 FUNCTION (<name>) NOT FOUND instead, as if it did not exist.
<user functions>: if 1 or 3, functions added with @function are refused too. Otherwise the list covers only built-in functions. Local functions are called through localfun(), so list localfun to refuse them.
<allow>: if 1, <functions> are the only ones allowed, and every other function is refused.

If <functions> is empty, <expression> is evaluated as usual. A sandbox() inside another keeps the outer one’s refusals, so it can only refuse more functions. Commands the expression queues, with trigger() or @wait for example, run later without the sandbox.

This function comes from RhostMUSH.

> think sandbox([add(1,1)] [sub(1,1)],add)
#-1 PERMISSION DENIED: CANNOT USE ADD 0
> think sandbox([add(1,1)] [sub(1,1)],add,0,0,1)
2 #-1 PERMISSION DENIED: CANNOT USE SUB

::: seealso

LOCALIZE()
@function :::