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Parse, don't validate (2019)

(lexi-lambda.github.io)
398 points declanhaigh | 1 comments | 07 Mar 23 08:47 UTC | HN request time: 0s | source
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bruce343434 ◴[07 Mar 23 10:54 UTC] No.35053912[source]▶
Note that this basically requires your language to have ergonomic support for sum types, immutable "data classes", pattern matching.

The point is to parse the input into a structure which always upholds the predicates you care about so you don't end up continuously defensively programming in ifs and asserts.

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jim-jim-jim ◴[07 Mar 23 11:15 UTC] No.35054070[source]▶
I think we'll eventually come to regard `if` as we do `goto`.
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leetrout ◴[07 Mar 23 11:48 UTC] No.35054298[source]▶
Using pattern matching instead or something else?
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1. Joeri ◴[07 Mar 23 12:00 UTC] No.35054371[source]▶
By using reactive programming techniques the program can be approached as a set of data streams mapping input to output, and conditional behavior becomes the application of different filters and combiners on the streams. This dovetails nicely with functional programming, which allows generic expression and reuse of those stream operations.