[J3] Question about the conditional expression syntax in 21-157r2

[Van Snyder]

On Thu, 2021-07-01 at 05:53 +0900, Malcolm Cohen via J3 wrote:
> Hi Milan,
>  
> Well, using ordinary parens instead of special parens was what I
> objected to.
>  
> But without any delimiter, there is ambiguity and a greatly increased
> risk of error.

I'm traveling, so I knew I couldn't participate in this meeting, so I
haven't studied the proposals. So the answers might be obvious.
Are parentheses required to avoid ambiguity if a conditional expression
is the entirety of an expression, such as1. An actual argument?2. The
RHS of an assignment statement?3. The <expr> in a IF statement?4. Can a
conditional form produce a variable, or only a value? Especially as an
actual argument?
>  
> So IMO,
>    special parens = best
>    ordinary parens = acceptable
>    no parens = unacceptable
>  
> Cheers,
> -- 
> ..............Malcolm Cohen, NAG Oxford/Tokyo.
>  
> From: J3 <j3-bounces at mailman.j3-fortran.org> On Behalf Of Milan
> Curcic via J3
> Sent: Thursday, July 1, 2021 2:54 AM
> To: General J3 interest list <j3 at mailman.j3-fortran.org>
> Cc: Milan Curcic <caomaco at gmail.com>
> Subject: [J3] Question about the conditional expression syntax in 21-
> 157r2
>  
> Hi Malcolm,
>  
> In 21-157r2, you wrote:
>  
> > Conditional expression with elseif-chaining:
> >     ( cond ? expr : cond2 ? expr2 : expr3 )
>  
> Are parens required? It seems to me that they don't need to be and we
> could write:
>  
> Conditional expression with elseif-chaining:
>      cond ? expr : cond2 ? expr2 : expr3
>  
> and if a programmer likes parens as a visual, they can add them.
>  
> What do you think?
>  
> Thanks,
> Milan
>  
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