Yes, the D language has that as a feature in function arguments!
replyhttps://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!
Props to D for having such a simple implementation of fexprs[1].
replyThe 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.
Or you could wrap arguments in lambdas (anonymous functions) for eagerly-evaluted languages. Lisp unfortunately has a bulky syntax for lambdas, compared to something like Smalltalk. Of course, you can fix this with reader macros in Common Lisp (but no one does). Clojure has a shorter syntax I believe as well: #().
replyYou could do that as well with lisp by passing around lambdas to functions but that adds unnecessary syntax.
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