Why is `pop' not named `npop'?

Why is `pop' not named `npop'?

[mbork]

Hi all,

the `pop' macro is destructive.  Why isn't it called `npop' then?  My
wild guess is that the `n-' prefix is only used for functions, not
macros, but is that really true?

Best,

-- 
Marcin Borkowski
https://mbork.pl
https://crimsonelevendelightpetrichor.net/

Re: Why is `pop' not named `npop'?

[Po Lu]

mbork@mbork.pl writes:

> Hi all,
>
> the `pop' macro is destructive.  Why isn't it called `npop' then?  My
> wild guess is that the `n-' prefix is only used for functions, not
> macros, but is that really true?
>
> Best,

If I were to guess, because `pop' does not modify the list itself, only
the value of the GV.

Re: Why is `pop' not named `npop'?

[Philip Kaludercic]

mbork@mbork.pl writes:

> Hi all,
>
> the `pop' macro is destructive.  Why isn't it called `npop' then?  My
> wild guess is that the `n-' prefix is only used for functions, not
> macros, but is that really true?

Not every name is consistent, but there is also no need for a
non-destructive pop since we already have car.

> Best,

Re: Why is `pop' not named `npop'?

[Emanuel Berg]

Philip Kaludercic wrote:

>> the `pop' macro is destructive. Why isn't it called `npop'
>> then? [...]
>
> Not every name is consistent

They sure ain't.

And "n" can also be for "not", e.g. `nlistp'.

So not pop, what would that be? Rock?

> but there is also no need for a non-destructive pop since we
> already have car.

But shouldn't `pop' be called "ncar" then?

-- 
underground experts united
https://dataswamp.org/~incal

Re: Why is `pop' not named `npop'?

[Yuri Khan]

On Wed, 17 Jan 2024 at 17:53, Emanuel Berg <incal@dataswamp.org> wrote:

> >> the `pop' macro is destructive. Why isn't it called `npop'
> >> then? [...]

> > but there is also no need for a non-destructive pop since we
> > already have car.
>
> But shouldn't `pop' be called "ncar" then?

The ‘n’ in ‘nreverse’ and other destructive functions is said to mean
‘non-consing’, that is, they won’t allocate new cons cells but rather
modify what is already there to achieve the desired structure. The
focus is not on destructiveness, it is on the lack of pressure on the
allocator.

‘car’ is already as non-consing as it gets.