Generalise associative operator parsing

This commit generalises parsing of associative operators from left-associative
only (with some ugly hacks to support right-associative assignment) to properly
left/right-associative operators.

Parsing still is not general enough to handle non-associative,
non-highest-precedence prefix or non-highest-precedence postfix operators (e.g.
`..` range syntax), though. That should be fixed in the future.

Lastly, this commit adds support for parsing right-associative `<-` (left arrow)
operator with precedence higher than assignment as the operator for placement-in
feature.

0 files changed, 0 insertions, 0 deletions