Overriding existing functions
Backport allows you to overwrite existing functions to fix bugs and increase/extend functionality.Availability
Backport.js v0.1 and above.
Syntax
Exactly the same as Adding missing functions.
Parameters
Exactly the same as Adding missing functions.
Return values
Exactly the same as Adding missing functions.
Examples
The key difference between adding a missing function and overriding an existing function is that in the case of overrides you'll almost certainly want to access native API features, in other words you'll probably still want to call the original function at some point via backport.global
or functionName.native
.
// Warzone 3.1 Beta 1 had a bug in pickStructLocation() // see http://forums.wz2100.net/viewtopic.php?f=35&t=8694 for details // Let's fix that bug... (function() { // We can work out if this bug is present by checking whether removeReticuleButton() is present // removeReticuleButton() was added to the JS API in the same version that the pickStructLocation() bug was fixed if (!backport.global.removeReticuleButton) { // the pickStructLocation() bug is present // define a new function that calls the original function then fixes it's return value backport("pickStructLocation",function(droid,structureType,x,y) { // apply the original (native) function var pos = pickStructLocation.native.apply(null,arguments); // the bug effected everything except cyborg factories if (structureType != "A0CyborgFactory") { pos.x += 1; pos.y += 1; } // return correct position back to calling script return pos; }); } })(); // thereafter, scripts can safely use pickStructLocation() without having to worry about offset bugs :)
See also
- Adding missing constants – most functions will rely on constants so need to make sure they are around
- Adding missing functions – how to add functions in cases where the native function doesn't exist
- How does Backport work? – learn more about what's going on under the hood