Perferr cond over case?

Perferr cond over case?

[Nordlöw]

Does the use of the cl macro case() incurr some loss of performance
compare to using cond() instead?

/Nordlöw

Re: Perferr cond over case?

[Pascal J. Bourguignon]

Nordlöw <per.nordlow@gmail.com> writes:

> Does the use of the cl macro case() incurr some loss of performance
> compare to using cond() instead?

(macroexpand '(case (* 2 2 2 2 3)
                (10      'one)
                ((24 42) 'two)
                ((3 33)  'three)
                (otherwise 'unknown)))
-->
(let ((--cl-var-- (* 2 2 2 2 3)))
    (cond ((eql --cl-var-- (quote 10)) (quote one))
          ((member* --cl-var-- (quote (24 42))) (quote two))
          ((member* --cl-var-- (quote (3 33))) (quote three))
          (t (quote unknown))))

What do you think?



-- 
__Pascal Bourguignon__

Re: Perferr cond over case?

[David Kastrup]

pjb@informatimago.com (Pascal J. Bourguignon) writes:

> Nordlöw <per.nordlow@gmail.com> writes:
>
>> Does the use of the cl macro case() incurr some loss of performance
>> compare to using cond() instead?
>
> (macroexpand '(case (* 2 2 2 2 3)
>                 (10      'one)
>                 ((24 42) 'two)
>                 ((3 33)  'three)
>                 (otherwise 'unknown)))
> -->
> (let ((--cl-var-- (* 2 2 2 2 3)))
>     (cond ((eql --cl-var-- (quote 10)) (quote one))
>           ((member* --cl-var-- (quote (24 42))) (quote two))
>           ((member* --cl-var-- (quote (3 33))) (quote three))
>           (t (quote unknown))))
>
> What do you think?

Before or after byte compilation?

-- 
David Kastrup