On Thu, Jul 9, 2009 at 7:08 PM, Walter Bright<[email protected]> wrote: > Jérôme M. Berger wrote: >> >> Walter Bright wrote: >>> >>> Nick Sabalausky wrote: >>>> >>>> "Walter Bright" <[email protected]> wrote in message >>>>> >>>>> It's handy when you want to prefix one expression to another, as in: >>>>> >>>>> (foo(), x + 3) >>>> >>>> I guess I'm not familiar with that syntax. What does that do and for >>>> what purpose? >>> >>> They're called Comma Expressions, and the left operand is evaluated >>> first, its result discarded, then the right operand is evaluated and forms >>> the type and result of the Comma Expression. >>> >> I've always felt they were useless and confusing. What's the advantage >> of "y = (foo(), x + 3);" over "foo(); y = x+3;"? > > When you only see the x+3 because you're recursively walking the tree > generating code.
If it's internal to the parse tree can't you make the syntax whatever you want? Something like (expr1 __exprSequencer expr2) should do just fine, right? No reason it has to be a precious one-character symbol syntax. --bb
