Allow match to use the continue keyword to allow for a switch-like continuation

[greenfox1505]

Describe the project you are working on

Just a GDScript feature request.

Describe the problem or limitation you are having in your project

match is a replacement for switch from other langauges. It is a much easier syntax for most of what people use switch for. It however doesn't allow some niche functionality that exists in switch, like triggering multiple code blocks for a single switch/match.

Describe the feature / enhancement and how it helps to overcome the problem or limitation

It allows a single match statement to have multiple effects without nesting match statements.

Describe how your proposal will work, with code, pseudo-code, mock-ups, and/or diagrams

func _ready():
	var x = {
		"name" : "Dennis",
		"age" : 45,
		"hair":"blue",
	}
	match x:
		{}:
			print("Empty dict")
		{"name": "Dennis"}:
			print("The name is Dennis")
		{"name": "Dennis", "age": var age,..}:
			print("Dennis is ", age, " years old.")
			continue #this would allow you to continue this match statement to the next check, similar to `switch`
		{"name": "Dennis", "hair": var color,..}:
			print("Dennis has ", color, " hair.")
		{"name", "age",..}:
			print("Has a name and an age, but it's not Dennis :(")
		{"key": "godotisawesome", ..}:
			print("I only checked for one entry and ignored the rest")

Currently godot only match the age value. But with a continue, he could match age and then continue to match color. It has the opposite effect of a break within switch. Or a similar effect as a continue in an for loop.

Without the continue line, the statement would output this:

Dennis is 45 years old.

With the continue line and langauge support, it could output:

Dennis is 45 years old.
Dennis has blue hair.

If this enhancement will not be used often, can it be worked around with a few lines of script?

It's a GDScript language feature. It can't easily be implemented with GDScript.

A similar effect would be difficult to manage without a nested match statement or similar control logic.

Is there a reason why this should be core and not an add-on in the asset library?

It's a GDScript language feature.

[greenfox1505]

I flipped through some old proposals, and launched Godot3 again for the first time in a while. Looks like this WAS a feature in Godot3. The above code works as expected unchanged in Godot3.5.3.

[dalexeev]

• See GDScript: Remove function of continue for match statement godot#71914.

If we want to add something like this, then it should be a separate keyword, not continue. fallthrough doesn't fit because it works differently in switch (executes the rest of the code without checking cases).

[theraot]

How about allowing another keyword to specify:

• continue while
• continue for
• break while
• break for

It might be useful in nseted loops, and continue match would not be an issue.

[greenfox1505]

I think continue makes pretty good sense in this context. In a loop it does the next thing, and in this it also does the next thing. switch in other languages use break to leave the statement

Unless we find a really good alternative, IMHO, it would cause more confusion than it's worth. I'm really not a fan of two word solutions.

• resume
• fallthrough
• continue

[dalexeev]

• See also Add fallthrough for match cases #160.