Brendan Eich wrote:
var y = (a) => a ? f : x++ (1);
evaluated (or is it syntactically valid at all)?
The problem with expression closures is precedence inversion: you have
LowPrec ~~> HighPrec ~~> stuff ending with LowPrec. The particular
nonterminals are AssignmentExpression and PrimaryExpression.
No such problem afflicts arrows, because they are low-precedence, in
fact AssignmentExpression alternative right-hand sides. So your
example here is a syntax error, because you are placing two assignment
expressions
I mean an assignment expression followed by a primary expression, of
course. The `(a) => a ? f : x++` arrow is an assignment expression, the
`(1)` is a separate expression. The `(1)` cannot be the actual parameter
list for the arrow unless you parenthesize the arrow to make it be a
MemberExpression (the highest precedence non-terminal that can be the
callee in a CallExpression).
Precedence, whee!
/be
next to one another with no operator or semicolon in between.
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