WoW:API pcall

pcall -Documentation by Darjk-

Returns a boolean value to catch errors from the function call (func).

retVal = pcall (func, arg1, arg2, ...);

Parameters

(func, arg1, arg2, ...)

func: Function - The function that will be called (from within) pcall().
arg1: Variable - Any variable that is also to be passed with the function when its called (if any).
arg2: Variable - Same as arg1.

retVal

retvaL: Boolean - If the call to the function (that was passed to pcall) succeeded, returns true. If an error occured, returns false.

function myTest()
  local strTest = "I am a string";
  strTest = strTest + 10;
end

local retVal = pcall(myTest());

pcall will catch the error that occured within 'myTest' and return false.

retVal = false;

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