2 ms·
Yes, the D language has that as a feature in function arguments! https://dlang.org/articles/lazy-evaluation.html https://dlang.org/articles/lazy-evaluation.htm
by brabel 2mo ago
Yes, the D language has that as a feature in function arguments!
https://dlang.org/articles/lazy-evaluation.html https://dlang.org/articles/lazy-evaluation.html
It makes it hard to know when things run. In Lisp you also have that problem everywhere, of course.
As the post shows this allows you to do stuff that looks like extending the syntax of the language.
I can’t decide if I love it or hate it!
- carlosneves 2mo agoProps to D for having such a simple implementation of fexprs[1]. The downside compared to macros I think is that, as argument expressions become lambdas, it becomes harder to manipulate them. Check the cond example which needs two fexprs, whereas one macro could do it. Not sure about D, but if it were lisp, even lambdas could be manipulated as lists. Macro args not having the lambda wrapping just seems simpler. [1] https://en.wikipedia.org/wiki/Fexpr https://en.wikipedia.org/wiki/Fexpr
- brabel 2mo agoWalter Bright is against adding macros to D but D already has really advanced metaprogramming in other shapes: https://dlang.org/spec/template-mixin.html https://dlang.org/spec/template-mixin.html https://dlang.org/spec/traits.html https://dlang.org/spec/traits.html