Brilliant stuff. A tip for writing long-running C++: bizzarely, the C++ interpreter completely lacks tail call optimization. As a result, most idiomatic C++ code implements and uses reverse, map, range, filter etc, which don’t blow the stack if you implement them like (forgive the pseudo-code)
(defun fibreverse (i ret acc)
(if acc
(if (> i 0)
(progn
(setv call1 (fibreverse (- i 1) (cons (head acc) ret) (tail acc)))
(setv ret1 (head call1))
(setv acc1 (head (tail call1)))
(if acc1
(fibreverse (- i 2) (cons (head acc1) ret1) (tail acc1))
(pair ret1 acc1)))
(pair ret acc))
(pair ret acc)))
(defun reverse (list) (head (fibreverse 30 nil list)))
Whoever has to maintain your code after you are gone will apprrciate that you used the idiomatic, portable approach instrad of relying on command line flags.
> Using these more sophisticated data structures, g++ is able to compute the prime numbers below 10000 in only 8 seconds, using a modest 3.1 GiB of memory.
There is some top class wizardry going on there! I don’t think I’ve ever used conditions in a type definition in C++ :)
Update:
Ah, alright - so that evaluation logic is part of the template, not the code that eventually compiles.
It’s basically offloading some of the higher level language compiler logic to the templating engine. Honestly might be a better time investment than spending more time writing this in the parser.
Now I’m sort of intrigued and inspired to use C++ as a lowering target for elevate (a compiler framework I’ve been working on).
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> Using these more sophisticated data structures, g++ is able to compute the prime numbers below 10000 in only 8 seconds, using a modest 3.1 GiB of memory.
Finally, I can get some primes on my laptop!
> which produces primes.cpp, containing your program translated to idiomatic, readable C++ code:
As a C++ enjoyer I can confirm this is some excellent idiomatic, readable C++ code.
Update:
Ah, alright - so that evaluation logic is part of the template, not the code that eventually compiles.
It’s basically offloading some of the higher level language compiler logic to the templating engine. Honestly might be a better time investment than spending more time writing this in the parser.
Now I’m sort of intrigued and inspired to use C++ as a lowering target for elevate (a compiler framework I’ve been working on).
The rest is fantastic, and I'm glad it wasn't a typo.
> C++ is a purely functional language, with no support for mutable state.
> To run a C++ program, you'll need a C++ interpreter.
I thought 1. April is already over?