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0 pointsknownjorbist4y ago0 comments

It's not insane, just dissimilar to what you're used to.

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5 comments · 2 top-level

creata4y ago· 3 in thread

Okay, it's not insane, it just breaks from a convention followed by practically every programming language (and every logic / engineering / computing course) where integers can be interpreted as booleans. And that might be okay if there's a good reason, but the reasons given are pretty awful:

https://news.ycombinator.com/item?id=11852434

nitrogen4y ago

Ruby is one popular example of a language with a truthy zero. This is to allow the use of truthiness to detect the presence of a value (as long as the value isn't false), even if the value is zero. Say I wanted to allow an environment variable to override a value in my code. I could do something like this:

    a = ENV['A']&.to_i || 1

and then run the program with A=0 to set a to 0.

jstanley4y ago

Perl has this too. The string "0 but true" is truthy, but is 0 as a numeric value.

(Any string starting with 0 that doesn't evaluate to a different number also works - but "0 but true" is specifically exempt from causing warnings).

DBI uses "0E0" instead, which I guess more reliably evaluates to 0 outside Perl, and still doesn't cause warnings.

int_19h4y ago

That approach is not unreasonable per se. But 1 being false is much harder to rationalize.

praptak4y ago

Dissimilarity for no good reason is, well, maybe not insanity but plain old dumb. Unless we're talking fashion not software projects, hence the "vanity" classification.

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