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Tryparse for union cases #1411

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6 tasks done
voronoipotato opened this issue Feb 25, 2025 · 2 comments
Open
6 tasks done

Tryparse for union cases #1411

voronoipotato opened this issue Feb 25, 2025 · 2 comments

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@voronoipotato
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voronoipotato commented Feb 25, 2025

For union cases without data types it would be nice if we had a default way to parse a string to cases.

type Bar = A | B 
let comparer (s: string) : int =  String.Compare(str, arg, StringComparison.InvariantCultureIgnoreCase)

let (a: Bar option) = Bar.tryParse "A"  //tryParse would be autogenerated by the compiler
let (b: Bar option) = Bar.tryParseWith comparer "b"

//alternatively
let (a': Bar option) = Union.tryParse<Bar> "A"
let (b': Bar option) = Union.tryParseWith<Bar> comparer "b"

Pros and Cons

The advantages: Less boilerplate for using Unions, standardized way for newbies to turn their strings into union cases

The disadvantages : Potential new union module, extra work, might entice people to make follow up suggestions related to this

Extra information

Estimated cost (XS, S, M, L, XL, XXL): S-M

Related suggestions:

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@voronoipotato
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Also for some reason the template for "new issues" wasn't putting the stuff in there. Not sure what that's about.

@T-Gro
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T-Gro commented Feb 25, 2025

Also for some reason the template for "new issues" wasn't putting the stuff in there. Not sure what that's about.

I will check that, thanks for letting us know

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