Re: Command Languages Versus Programming Languages

On 2024-04-05, Alan Bawden <alan@csail.mit.edu> wrote:

Lawrence D'Oliveiro <ldo@nz.invalid> writes:
>
   On Fri, 5 Apr 2024 09:17:37 -0000 (UTC), Muttley wrote:
   ...
   >>    a =
   >>        b ?
   >>            c ? d : e
   >>        : f ?
   >>            g ? h : i
   >>        : j;
   >
   > Just use brackets. Saves a lot of pain.
>
       a=(b?(c?d:e):(f?(g?h:i):j));
>
A normal programmer would write something like:
>
    a = b ? (c ? d : e) :
        f ? (g ? h : i) :
        j;
>
I.e., she would allow herself to use spaces and newlines, and just
enough parentheses to make the structure clear.

It looks good, undeniably.

However, I cannot tell at a glance whether or not the nice appearance
isn't telling me some kind of lie. That's an inherent problem with
the ternary operator.

I have to remember that = has lower precedence than ?:. But, ==
has higher precedence. So this careless edit makes it wrong,
even though it still looks just as nice:

      a == b ? (c ? d : e) :
           f ? (g ? h : i) :
           j;

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