When I was writing code with GroupEnumUnitsXXX natives, I found out that they require a valid group parameter. Creating temporary group every time whenever I needed to enum units was definitely messy. Otherwise, I had to use globals block to define a single private dummy group for each library. So I came up with the idea of writing a library that contains every element needed.
This library greatly simplifies process to enum units. You don't have to worry about anything about groups. It also eliminates the need of creating a filter every time (or defining a global for it).
Using it is extremely easy. All you need is a callback function that matches the signature. You can see it in the example below.
Example Code:
function MyCallback takes unit u returns nothing
call BJDebugMsg(GetUnitName(u))
endfunction
call EnumUnitsOfPlayer(GetTriggerPlayer(), MyCallback)
Very simple, isn't it?
There are two styles: .execute and .evaluate. The only difference is one line of code, but you should be aware of the differences:
.execute style allows waits inside callbacks, while .evaluate style runs faster but doesn't allow waits inside callbacks.
Library Code (.execute):
library EnumUtils initializer init
public function interface callback takes unit enumUnit returns nothing
globals
private group g
private boolexpr filterEnumUnits
private callback enum_cb
endglobals
function EnumUnitsInRange takes real x, real y, real radius, callback cb returns nothing
set enum_cb = cb
call GroupEnumUnitsInRange(g, x, y, radius, filterEnumUnits)
endfunction
function EnumUnitsInRect takes rect r, callback cb returns nothing
set enum_cb = cb
call GroupEnumUnitsInRect(g, r, filterEnumUnits)
endfunction
function EnumUnitsOfPlayer takes player whichPlayer, callback cb returns nothing
set enum_cb = cb
call GroupEnumUnitsOfPlayer(g, whichPlayer, filterEnumUnits)
endfunction
private function EnumerateUnits takes nothing returns boolean
call enum_cb.execute(GetFilterUnit())
return false
endfunction
private function init takes nothing returns nothing
set g = CreateGroup()
set filterEnumUnits = Filter(function EnumerateUnits)
endfunction
endlibrary Library Code (.evaluate):
library EnumUtils initializer init
public function interface callback takes unit enumUnit returns nothing
globals
private group g
private boolexpr filterEnumUnits
private callback enum_cb
endglobals
function EnumUnitsInRange takes real x, real y, real radius, callback cb returns nothing
set enum_cb = cb
call GroupEnumUnitsInRange(g, x, y, radius, filterEnumUnits)
endfunction
function EnumUnitsInRect takes rect r, callback cb returns nothing
set enum_cb = cb
call GroupEnumUnitsInRect(g, r, filterEnumUnits)
endfunction
function EnumUnitsOfPlayer takes player whichPlayer, callback cb returns nothing
set enum_cb = cb
call GroupEnumUnitsOfPlayer(g, whichPlayer, filterEnumUnits)
endfunction
private function EnumerateUnits takes nothing returns boolean
call enum_cb.evaluate(GetFilterUnit())
return false
endfunction
private function init takes nothing returns nothing
set g = CreateGroup()
set filterEnumUnits = Filter(function EnumerateUnits)
endfunction
endlibrary
