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In-line functions in .mcfunction files

If, in a .mcfunction file, you want to execute multiple commands depending on some condition, the following is required:

execute if <condition> run function namespace:some_function

# Function namespace:some_function
say Hello world!
give @s minecraft:diamond 64

Note that this requires two .mcfunction files. In most traditional programming languages, however, the following would be possible

if (<condition>) {
    <statement>
}

I propose adding a similar syntax to .mcfunction files, allowing for in-line functions, making situations such as conditional statements or executing several commands as/at a group of entities significantly easier and more concise.

execute if <condition> run function {
    say Hello world!
    give @s minecraft:diamond 64
}

execute as @e[type=minecraft:cow] at @s run function {
    data modify entity @s Motion[1] set value 5.0f
    particle minecraft:cloud ~ ~ ~ 0 0 0 0.1 10 normal
}

There are already user-made transpilers and variations of the mcfunction language allowing for in-line functions, thus proving that there is indeed a part of the community that would be interested in such a change, and natively supporting this within .mcfunction files would make life for a lot of datapack developers a lot easier.

Registered User shared this idea

• March 25, 2021 18:35
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  • March 27, 2021 03:36
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  I'll second this post because of the ability to have it all in one function. In the meantime we could have a check before each step of the inner function:

  execute as @e[type=cow] at @s run say Step 1
  execute as @e[type=cow] at @s run say Step 2

  But it is much more cumbersome to write and it messes up the collation of the steps, so that's why I agree with this post.

  I'm afraid I don't agree with the syntax for blocks though, braces {} seem too far deviated from Minecraft command syntax. Instead of that, I'd like to propose indentation blocks like in the language Python to show this. Indent should be one tab per indentation level. This renders as eight spaces here but many notepad editors allow customization:

  execute if <condition> run commands
  	say Hello world!
  	give @s minecraft:diamond 64

  execute as @e[type=minecraft:cow] at @s run commands
  	data modify entity @s Motion[1] set value 5.0f
  	particle minecraft:cloud ~ ~ ~ 0 0 0 0.1 10 normal

  The word commands can be anything, but it is required because I think you should be required to indicate when you are about to start an indented block, and a key word that activates it would best fit in with current command syntax.

  As for word choice, I thought of something that would make sense if you said it out loud (… if this condition is true, run the commands …) and I didn't want to use function because it was already taken. Feel free to suggest another word.