I'd like to be able to offer extensible infix operators so
you'd be able to write something like:
c = a func b
This would be evaluated as:
c = func(a, b)
As explained in the answers, that would be ambiguous; I proposed a more-or-less working metalua macro, allowing Haskell syntax (when you put a function between backquote `like_this`, it becomes infix,
e.g. "2 `plus` 2"), which had many quirks, mainly due to then-unimplemented metalua features. Here is a properly working extension (works with metalua 0.2):
-{ block:
local if_prec = 35 -- precedence of infix functions
local if_expr = |lx| mlp.expr (lx, if_prec)
mlp.expr.add_postfix_sequence{
"`", if_expr, "`", if_expr,
prec = if_prec, builder = |x| `Call{ x[2], x[1], x[3] } } }
This one properly handles precedence, and is left-associative. For insights of how it works, look at the "sugar.lua" sample on metalua website.
