setstackhidden(fnOrLevel?, hidden?) / sethiddenstack / set_stack_hidden

Hides a closure from stack inspection; hidden functions also lose their error location prefix.

Syntax

setstackhidden(fn: function | level: number, hidden: boolean?) -> ()

Parameters

Parameter	Type	Description
`fn/level`	`function \| number`	Closure or stack level to hide.
`hidden`	`boolean`	Defaults to true.

Returns

Type	Description
`()`	No direct return values.

Description

Hidden closures are removed from debug.info/debug.traceback results and from the GC-visible closure set.

Logic change: the executor error hook now inspects the requested level and passes level 0 to the original error when that frame is a hidden closure. error("message", 2) from a hidden caller therefore produces exactly "message" with no [string] prefix.

Example

local function hiddenCaller() error("debUNC", 2) end
setstackhidden(hiddenCaller, true)
print(select(2, pcall(hiddenCaller))) -- debUNC

Notes

Return value behavior of debug.info and debug.traceback is unchanged.