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4:34:50
moon-child
so, in s7 scheme, there's a form let-temporarily, which can be used to approximate dynamic scoping
4:35:15
moon-child
essentially, (let-temporarily ((x y)) ...) is the same as (let ((old-x x)) (set! x y) ... (set! x old-x))
4:35:52
moon-child
one of the things that's nice about this is that it can be used with arbitrary locatives. So for instance (let-temporarily (((car x) y)) ...) will do the obvious thing
4:36:18
moon-child
wouldn't it be nice if we could have a form like 'let-lexically', which would also work with arbitrary locatives?
4:36:48
moon-child
so for instance, (define x (list 1)) (define (f) (car x)) (let-lexically (((car x) 2)) (f)) --> 1, because f is not in the same lexical scope
4:37:07
moon-child
or: (define x (list 1)) (let-lexically (((car x) 2)) (car x)) --> 1, because car is not in the same lexical scope
4:38:06
moon-child
in other words, this feature can be implemented at _no_ performance cost at all by simply mapping to a no-op at compile time!
4:44:05
loke[m]
moon-child: this is a joke right? Because I just spent fat too much time understanding this, to figure out how this could ever be useful. :-)
5:21:51
moon-child
RRRRedEye[m]: I assumed uiop meant that the freenode channels were not gone, even through freenode ~is
5:22:07
moon-child
talismanick: what is 'lisp'? No implementation I know of supports them natively, but you can of course implement them
5:23:08
moon-child
talismanick: you may be interested in https://github.com/stylewarning/computable-reals, then
5:24:10
talismanick
That sounds like a clickbait title for a potentially interesting talk/paper, though
5:44:39
RRRRedEye[m]
how to diff it? i installed sbcl but i can't said i'm using the x86_64 sbcl(even i'm using the x86_64 archlinux with guix)
5:46:02
uiop
it must be x86_64, on mac you run `file sbcl` and it will tell you the architecture of the binary file
7:23:16
pjb
talismanick: only PI is recomputed when the length is changed; your own values will keep their precision.
7:23:51
pjb
talismanick: but this shows the difficulty of expanding the numeric tower in CL. This breaks often a lot of assumption, like PI is a constant variable.