Weird Operator Behavior

[STRd6]

operator min

min 1, 2
min 1, 2

Becomes:

min(1, min(2, 1), 2);

It should be:

min(1, 2)
min(1, 2)

Adding semi-colons or assignments fixes it.

https://civet.dev/playground?code=b3BlcmF0b3IgbWluCgptaW4gMSwgMgptaW4gMSwgMg%3D%3D

[edemaine]

Fair point; that definitely seems confusing.

We currently allow binary operators at starts of lines to continue lines. For example:

x := 5
- x
or y
---
const x = 5 - x || y

I think this makes sense for symbol operators, and probably other built-in operators like and and or, because it couldn't mean anything else (in particular because - x currently cannot be interpreted as a unary -). For comparison, this isn't supported in CoffeeScript but part of it was proposed in jashkenas/coffeescript#5279

Perhaps custom operators should allow this only when they are IndentedFurther. So if you intended the current compilation of your example, you could write it this way:

min 1, 2
  min 1, 2

[STRd6]

I don't think it makes sense for our current custom operators since they are not infix, but it could make sense if they were.

[edemaine]

What do you mean that they're not infix? operator is specifically for making infix operators. Do you mean that they're optionally infix?

[STRd6]

You're correct, I had a moment of confusion.

The optionally infix is what I think this makes this behavior weird. I can see allowing your example of using IndentedFurther to match a custom operator as infix but it probably shouldn't match as infix if on the next line at the same level of indentation.

min 1, 2
  min 1, 2

Has this as a sensible parse:

min(1, min(2
  1), 2)

min 1, 2
min 1, 2

Should parse like this:

min(1, 2)
min(1, 2)