Greedy strings cannot contain trailing spaces in a function

Partially fixed in 23w31a, thanks to macros. We can now generate commands that start and/or end with spaces as follows:

1. Load the following macro

mc-174587:macro

$advancement grant @s only mc-174587:test $(criterion)
execute if entity @s[advancements={mc-174587:test=true}] run say granted
execute if entity @s[advancements={mc-174587:test=false}] run say revoked

1. Run the following command

   function mc-174587:macro {criterion: "criterion with a trailing space "}

   → ✔ granted

Considering the overhead of macros, I would also like this to be achievable with just a function though.

Fixed in 23w31a. I have just noticed that we can include trailing spaces in a function by writing spaces followed by \ and leaving the next line empty as follows:

advancement grant @s only mc-174587:test criterion with a trailing space \

execute if entity @s[advancements={mc-174587:test=true}] run say granted
execute if entity @s[advancements={mc-174587:test=false}] run say revoked

→ ✔ granted

That's not fixed, that's a workaround; lines still cannot end with spaces. Your function's line ends with a "continue on next line", not a trailing space.

Yes, indeed, this is just making it non-trailing by guarding the trailing spaces with a \. It doesn't seem right that trailing trim and greedy strings coexist, but when such a purely syntactic workaround emerges, this issue might be considered as a feature request, like MC-264999. I'd like to leave the decision to the moderators and developers.