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Comment by dnautics | Hacker News Reader

If (a == 3) || (b == 4) delete it

Which one?

The propositions that are true. If a or b delete it becomes weird when both are true, because in conventional programming languages, b often isn't executed at all, since we don't care about the value of it. However, in this case you do need to execute it because you have to know if delete it reflects on a or both a and b.

If you want to delete both if either is true you could write:

  If (a == 3) || (b == 4) delete them

what if you want to delete a on the b condition?

If there's one condition, use `it`. If there's two, use `this` and `that`, i.e.

  if (a == 3) || (b == 4) delete this //to delete a

and

  if (a == 3) || (b == 4) delete that //to delete b

What if there are three?

Also this should refer to the temporally closer element, so your choices are backwards.

Instead of `it` for one, and `this` and `that` for two, use `este`, `ese` and `aquel` for three (from the 3-tier pronoun system in Spanish).

Please don't ask what if there's four. Very few (if any) natural languages have more than 3 tiers of demontrative pronouns, so computer languages shouldn't -- if they're using ideas natural language to be more readable. They would use identifiers or numeric subscripts instead.

In TXR Lisp, I came up with an anaphoric "if" called ifa which is quite different from Paul Graham's aif:

https://www.nongnu.org/txr/txr-manpage.html#N-018F39B0

"If two or more arguments are it-candidates, the situation is ambiguous. The ifa expression is ill-formed and throws an exception at macro-expansion time." [Rule 2]

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