optional first |

[scarf005]

it would be nice to be able to use

NUMBER_TYPE : 
    | INTEGER_TYPE
    | UNSIGNED_TYPE
    | FLOAT_TYPE

over current syntax.

NUMBER_TYPE : INTEGER_TYPE
    | UNSIGNED_TYPE
    | FLOAT_TYPE

i wonder if there's any technological difficulties for supporting optional first pipe symbol?

[MegaIng]

If you do this in a single line, it doesn't mean the same, i.e. it also accepts the empty expression. (see #1077) I could have sworn there also is a discussion somewhere about a different multi-line syntax where what you are proposing was one of the suggestions, but I can't find it.

[erezsh]

Do you mean this one? #155

[scarf005]

well, this is certainly a confusing behavior and i can't find out anything about docs.
i think empty expression should be more explicit.

[MegaIng]

@erezsh Yes

@scarf005 It's just a consequence of the way the grammar syntax works, no special casing is happening.

[scarf005]

@MegaIng well then the way the grammar syntax works should be more explicitly documented, because i could not find out what would happen if the rule is empty. (try ctrl-f empty on docs)