Change 1489
Revert syntax of "expr : expr `in` expr" to jam 2.3's
"expr : arg `in` list", because:
a) It broke the precedence of `in` so that it was looser than
!, parsing "! xxxx in yyy" as '( ! xxx ) in yyy".
b) It didn't allow providing an in line list as "$(f) in a b c".
Change to unreleased behavior.
"expr : arg `in` list", because:
a) It broke the precedence of `in` so that it was looser than
!, parsing "! xxxx in yyy" as '( ! xxx ) in yyy".
b) It didn't allow providing an in line list as "$(f) in a b c".
Change to unreleased behavior.