On Sunday, 17 October 2021 at 21:17:43 UTC, Paulo Pinto wrote:
> The very first compiler for Lisp was created in 1960 for the IBM 704.
Common Lisp was just one example among others, here are a few more.
- Dylan, released to the public in 1995
AKA, Common Lisp.
>
- Template Haskell, initially prototyped in 2002
I don't know of your other examples, but Common Lisp and Template Haskell are in the category with C++ templates of "this could be technically abused towards compile time evaluation (which still isn't ctfe) if someone wanted to, but people generally didn't because it didn't occur to them".
I gave an example of a trivial macro earlier. It's from https://letoverlambda.com/lol-orig.lisp , where it's preceded by
(defun sleep-units% (value unit)
(sleep
(* value
(case unit
((s) 1)
((m) 60)
((h) 3600)
((d) 86400)
((ms) 1/1000)
((us) 1/1000000)))))
A normal function. Which was not simply used at compile-time; instead, a macro version was written so that the same calculation could occur at compile-time. And this is what people'd tend to do in Common Lisp. The function actually could be used at compile-time but the EVAL-WHEN syntax to do that is so heavy, nobody would bother without ctfe having occurred to them.
An example of a language where people genuinely did write normal functions and then freely execute them at compile-time is Forth, and there the community mostly bemoaned that poor optimizers made it necessary to use even for constant-folding:
: rotchar ( c -- c' )
dup [char] a [ char m 1+ ] literal within 13 and
over [char] A [ char M 1+ ] literal within 13 and +
over [char] n [ char z 1+ ] literal within -13 and +
over [char] N [ char Z 1+ ] literal within -13 and + + ;
WITHIN checks a half-open range, so it's getting passed 'a' and 'z'+1, with compile-time calculation of the latter happening due to [ ... ] literal
When a better optimizer is available you'd just write 'a' 'z' 1+ within
> It is useless for the community to whine who did it first, because it won't increase its audience.
This is a really strange axe to grind.
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