Very weird behaviour with enums and map() function

Help Programming
1

Godot Version

4.4

Question

I have this enum:

enum actions {
	FRONT_KICK,
	SPIN_KICK,
	UPPERCUT,
	DOWNWARDS_PUNCH,
	JUMP
}

And this function that takes as an argument one value of the enum:

func get_action_string(attack: Globals.actions) -> String:
	match attack:
		Globals.actions.FRONT_KICK:
			return 'front_kick'
		Globals.actions.SPIN_KICK:
			return 'spin_kick'
		Globals.actions.UPPERCUT:
			return 'uppercut'
		Globals.actions.DOWNWARDS_PUNCH:
			return 'downwards_punch'
		Globals.actions.JUMP:
			return 'jump'
		_:
			return ''

I want to check whether a string is an action in my enum (meaning that get_action_string() returns it), so I wrote this:

if text in Globals.actions.values().map(func(value): get_action_string(value)):
   print('yes it is')

But that doesn’t work (it never prints ‘yes it is’) even for strings I know 100% are related to my enum. In order to find out what was wrong, I printed this:

print(Globals.actions.values())
print(get_action_string(0), ' ', 0 in Globals.actions.values())
print(get_action_string(1), ' ', 1 in Globals.actions.values())
print(get_action_string(2), ' ', 2 in Globals.actions.values())
print(get_action_string(3), ' ', 3 in Globals.actions.values())
print(get_action_string(4), ' ', 4 in Globals.actions.values())
print(Globals.actions.values().map(func(value): get_action_string(value)))

And the output really surprised me!!!

[0, 1, 2, 3, 4]
front_kick true
spin_kick true
uppercut true
downwards_punch true
jump true
[<null>, <null>, <null>, <null>, <null>]

From what I see in the printed text, Globals.actions.values() returns the values that are accepted by the get_action_string() function. Therefore, how is it possible that the map() function can’t build an array with the strings returned by get_action_string()?

I know that there are severals workarounds for this and I’m not worried about it, but this issue makes me think that maybe I don’t know how enums or the map() function actually work in Godot.

Thanks!

2

You need to explicitly return from a lambda function: GDScript reference — Godot Engine (stable) documentation in English

1 Like
3

Btw. it’s also worth mentioning that since your signature matches the one expected by the map function you can skip the lambda function completly and pass the function directly:

Globals.actions.values().map(get_action_string)
1 Like
4

Good point, thx for the help!