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tialaramex • today at 5:56 PM • 1 reply • view on HN

I understand where you're coming from, but these terms seem fine to me:

This is exactly what, for example, Rust's str::parse method is for. The documentation gives the example:

    let four: u32 = "4".parse().unwrap();
You will so very often have text and want typed information, and parse is exactly how we do that transformation exactly once. Whereas validation is what it looks like when we try to make piecemeal checks later.

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lock1 • today at 7:43 PM

Coming from a more "average imperative" background like C and Java, outside of compiler or serde context, I don't think "parse" is a frequently used term there. The idea of "checking values to see whether they fulfill our expectations or not" is often called "validating" there.

So I believe the "Parse, Don't Validate" catchphrase means nothing, if not confusing, to most developers. "Does it mean this 'parse' operation doesn't 'validate' their input? How do you even perform 'validation' then?" is one of several questions that popped up in my head the first time I read the catchphrase prior to Haskell exposure.

Something like "Utilize your type system" probably makes much more sense for them. Then just show the difference between `ValidatedType validate(RawType)` vs `void RawType::validate() throws ParseError`.