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Parse, Don't Validate (2019)

(lexi-lambda.github.io)
389 points melse | 2 comments | 26 Jun 21 07:23 UTC | HN request time: 0s | source
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ukj ◴[26 Jun 21 07:47 UTC] No.27639995[source]▶
Software Engineers: Parse, don't validate.

Mathematicians: Parsing is validation

https://gallais.github.io/pdf/draft_sigbovik21.pdf

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pwdisswordfish8 ◴[26 Jun 21 08:05 UTC] No.27640078[source]▶
The point being, the converse of ‘parsing is validation’ is not true.
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ukj ◴[26 Jun 21 08:13 UTC] No.27640111[source]▶
The word "is" implies an isomorphism.

If you see it differently you are implicitly assuming a non-formalist perspective on what "validation" means. Tell us about it.

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pwdisswordfish8 ◴[26 Jun 21 08:29 UTC] No.27640177[source]▶
‘A square is a rectangle’ means squares are isomorphic to rectangles?
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ukj ◴[26 Jun 21 08:47 UTC] No.27640269[source]▶
You are tripping up over polymorphism. "Is" means many things - which meaning you infer is precisely parsing!

"A square is a rectangle" means "A square is a TYPE of rectangle" (at least, that is what I am parsing it as).

"Parsing is Validation" means Parsing is isomorphic to Validation.

How do I know? Because that is how I want you to parse it.

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jhgb ◴[26 Jun 21 13:57 UTC] No.27641887[source]▶
> "A square is a rectangle" means "A square is a TYPE of rectangle" (at least, that is what I am parsing it as).

In that case your former statement that 'The word "is" implies an isomorphism' seems to be wrong.

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1. ukj ◴[26 Jun 21 19:48 UTC] No.27645179[source]▶
It may be wrong in your model/interpretation of my words, but it's not wrong in my interpretation of my words.
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2. jhgb ◴[27 Jun 21 21:15 UTC] No.27655456[source]▶
In what interpretation is it consistent for 'A square is a rectangle" means "A square is a TYPE of rectangle"' and 'The word "is" implies an isomorphism' to be simultaneously true? No matter how I cut it, the latter seems to prevent the former to me.