Re: Dereferencing and style guides

[Bill Findlay <yaldnif.w@blueyonder.co.uk>]

On 10/10/2013 23:49, in article wcchaco3fne.fsf@shell01.TheWorld.com,
"Robert A Duff" <bobduff@shell01.TheWorld.com> wrote:

> Adam Beneschan <adambeneschan@aol.com> writes:
> 
>> I can imagine that Ada might have adopted the same syntax, if only
>> those old keypunch machines had a ^ character on them.
> 
> I thought they did.  Except it looked like an up-arrow.
> 
> Anyway, the solution to keyboards with missing characters
> is clear: see J.2.  7-bit ASCII was standard at the time.
> 
>> On the other hand, I'm not sure about the idea that "making things
>> just one character" equates to readability.  If that were true, APL
>> would be the most readable language around.  And C would be second.
> 
> Well, I didn't say everything should be one character.  I said
> the dereference operator should be one character.  So I'd say
> APL is a bit of a straw man here.  I'm quite happy to say
> "end if;" where C says "}".
> 
> In Ada, dereference is usually zero characters, so I'm actually arguing
> for MORE verbosity!  Just a little more.

Can I make the contrary case?

Given that we know that P is a pointer, P.f or P(i) can only reasonably be
interpreted as dereferencing P and selecting a component from the result; so
I do not see that P^.f or P^(i) improves comprehensibility to any
significant degree.

Given that we do not know that P is a pointer, P.f or P(i) is essentially
the same cognitive burden as R.f or A(i); from the uniform referent point of
view this is an advantage.  It fails to be, only if the dereference fails,
and we know that that should not happen in Ada 8-).  Even if it does, the
extra effort of perceiving the semantics correctly is trivial.

-- 
Bill Findlay
with blueyonder.co.uk;
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