API pcall

Calls a function, returning a boolean indicating success as the first return value, and error text / return values as the following values. retOK, ret1, ret2, ... retn = pcall (func, arg1, arg2, ...);

Arguments

 * func : Function - The function that will be called (from within) pcall.
 * arg1 - argn : Variable - Any variable that is also to be passed with the function when its called (Optional).

Returns

 * retOK : Boolean - If the call to the function (that was passed to pcall) succeeded, returns true. If an error occured, returns false.
 * ret1 : String (if failed) / Variable - If an error occured, error text is returned; if not, ret1 is the first return value of the original function.
 * ret2 - retn : Variable - If the function call succeeded, those return variables contain values returned by original function.

Example
function myTest(incrementVal) return incrementVal + 10; end local retOK, ret1 = pcall(myTest,"string value"); local msg = ""; if (retOK) then msg = "Function succeeded, result: " .. ret1 .. "."; else msg = "Function failed, error text: " .. ret1 .. "."; end DEFAULT_CHAT_FRAME:AddMessage(msg);

Result
pcall will catch the error that occured within 'myTest', and output the appropriate text to the default chat window. If "string value" is replaced by a number, the code will output number+10 instead.

Details

 * pcall will also return other arguments returned from the "function" if all is successful.