Re: pure-fns in byte-opt.el

[Mark Oteiza <mvoteiza@udel.edu>]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

>> (let ((pure-fns
>> -       '(concat symbol-name regexp-opt regexp-quote string-to-syntax)))
>> +       '(concat symbol-name regexp-opt regexp-quote string-to-syntax
>> +         make-vector)))
>
> Ah, now that makes a lot more sense: make-vector is much less pure than
> string-to-char.  The above will cause the compiler to replace
>
>    (make-vector 2 ?a)
>
> with
>
>    [?a ?a]
>
> so you end with a single immediate vector being re-used over and over,
> instead of having a new vector created each time.

But reading a literal vector still generates a new vector, no?