Re: novice: mapcan use?



Pascal Costanza wrote:
It cannot be stressed enough: Don't use the destructive functions as your regular tools, and better forget completely about them in the beginning. They should be used exactly like the non-destructive versions, and only ever for optimizations. There's no other advantage in using them, and you should only optimize those parts of your code that you have measured before so that you know that optimizations actually buys you anything. Everything else is a waste of your (valuable!) development time.

Rubbish. That is a defense of ignorance, and a recipe for newbies writing code so painfully slow they abandon Lisp.

/Always/ use the destructive version if one can get away with it. Understanding when one can get away with it is not so hard, and requires no more than the same understanding one needs anyway to program in Lisp.

We should place a Graham Tax on remove, append, and their ilk.

--
Kenny

Why Lisp? http://lisp.tech.coop/RtL%20Highlight%20Film

"I've wrestled with reality for 35 years, Doctor, and I'm happy to state I finally won out over it."
Elwood P. Dowd, "Harvey", 1950

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