How could you call a function from an array using a string?

Asked by

8 years ago

Edited 8 years ago

Is there a way to call functions from an array using strings? This is what I've tried and it hasn't been working out.

GameModeModule:

01local GameModes = {};
02 
03GameModes.SingleBattle = function()
04    print("Single battle!");
05end
06 
07GameModes.DoubleBattle = function()
08    print("Double battle!");
09end
10 
11function GameModes:Run(gameMode)
12    local func = module[gameMode];
13    return function()
14        func();
15    end
16end
17return GameModes;

server-script:

1local GameModes = require(script.GameModeModule);
2local GameModeTypes =
3{
4    SingleBattle = "SingleBattle",
5    DoubleBattle = "DoubleBattle"
6}
7 
8module:Run(GameModeTypes.SingleBattle);

Returning functions

When you return a function, you're still returning something that needs to be called. It doesn't get executed during the return process. To fix your problem, you could just call it on the same line as your "Run" method with two parenthesis ()

1local GameModes = require(script.GameModeModule);
2local GameModeTypes =
3{
4    SingleBattle = "SingleBattle",
5    DoubleBattle = "DoubleBattle"
6}
7 
8GameModes:Run(GameModeTypes.SingleBattle)() -- Calling the returned function

However

While this does solve your problem, it also isn't very necessary (not in this case, that is). Instead of returning a function, you should just execute the function you pass as the argument as soon as it's called. Here'd be a better example:

01local GameModes = {};
02 
03GameModes.SingleBattle = function()
04    print("Single battle!");
05end
06 
07GameModes.DoubleBattle = function()
08    print("Double battle!");
09end
10 
11function GameModes:Run(gameMode)
12    local func = GameModes[gameMode]
13    if func then -- Maybe just check if it exists as well
14        return func() -- Return whatever 'func' returns, while also executing it
15    else
16        print(tostring(gameMode) .. " is not valid") -- error message to help us know if something went wrong
17    end
18end
19 
20return GameModes;

1local GameModes = require(script.GameModeModule);
2local GameModeTypes =
3{
4    SingleBattle = "SingleBattle",
5    DoubleBattle = "DoubleBattle"
6}
7 
8GameModes:Run(GameModeTypes.SingleBattle)

Hope this helped, let me know if you have any questions.

How could you call a function from an array using a string?

1 answer

Yes

Returning functions

However

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