food for thought - swift 5 released - bottom types, string interpolation, and stuff.

[aliak]

On Friday, 12 April 2019 at 11:12:55 UTC, Walter Bright wrote:
> On 4/11/2019 11:52 PM, aliak wrote:
>> isOdd would've made the call site a lot more clear.
>
> Feel free to add such a function to your code.
>
>
>> Using n & 1 has always been a hack for oddness. It says 
>> nothing about what your code is doing.
>
> isOdd() doesn't say what your code is doing, either.
>
>
>> The average programmer would look at it and have to think 
>> about what's happening there.
>
> I'm happy to elevate them to the next level with such thoughts 
> :-)

🖖:)

>
>
>> But after all this time working on products as low level as 
>> drivers to as high level as web apps, the three things that 
>> have been the most important have been readability, 
>> maintainability, and correctness.
>
> (x & 1) isn't any harder to read than (x + 1).

Maybe, dunno. I can see that x + 1 means "i add one to x", and 
that x & 1 means "I'm masking out the bit pattern of 1 from x". 
For the former, you can derive that "oh, that means the next 
index" (i.e. if(x.nextIndex) and for the latter, you can derive 
that "oh only odd numbers will have a value of one" (i.e. 
x.isodd). But the derivations are more secondary thoughts implied 
by the initial operation. So I can see the difference as well. 
Granted they're certainly not harder to read, but I do think they 
are not exactly the same.

>
> More bluntly, it'll be hard for someone to succeed with D if 
> they have only a vague understanding of what 2's complement 
> arithmetic is, and a conceptual problem with the & operator. 
> isOdd() isn't going to fix that for them.

Can't argue with that :)