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1. IllusionMH commented on Feb 14, 2022

   

   Andrii Dieiev (IllusionMH)

   on Feb 14, 2022

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   What if instead of trying shorter cryptic type that starts with 3 strings and ends with 2 numbers (no idea what API can be described this way, instead of an object), it was tuple with labeled elements so any user will know correct order of some strings and some numbers, not only type and count?
2. jcalz commented on Feb 14, 2022

   

   Joe Calzaretta (jcalz)

   on Feb 14, 2022

   Last edited by jcalz

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   It's weird that the only use case listed for this is the same as the motivating example. Is there some actual real-world situation where tuples like this are being used that are so long as to be hard to use? I'd expect a motivating example to be like [string * 17, number * 7] or something, and a use case to be... like, some description of where such a monstrosity would actually be used.

   Aaanyway, given that #26223 is closed as fixed you can do something like this yourself without too much trouble and without extra syntax:

   type ArrayWithLengthFive = [...TupLen<3, string>, ...TupLen<2, number>];
   // type ArrayWithLengthFive = [string, string, string, number, number]
   
   type LenTwentyFour = [...TupLen<17, string>, ...TupLen<7, number>];
   // type LenTwentyFour = [string, string, string, string, string, string, string, 
   //    string, string, string, string, string, string, string, 
   //    string, string, string, number, number, number, number, number, number, number];

   🛠⚙

   type TupLen<N extends number, T = any, A extends T[] = []> =
   	N extends A['length'] ? A : TupLen<N, T, [T, ...A]>;

   Playground link

   👍React with 👍3Reacted by Ryan Cavanaugh, Homa Wong and Ricardo Fernández Serrata

   👀React with 👀1Reacted by Ricardo Fernández Serrata
3. fatcerberus commented on Feb 14, 2022

   

   Bruce Pascoe (fatcerberus)

   on Feb 14, 2022

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   [string * 17, number * 7]

   This is terrifying

   😄React with 😄4Reacted by Ryan Cavanaugh, Ricardo Fernández Serrata, Simon Sassi and snarbles2
4. Ryan Cavanaugh (RyanCavanaugh)

   added

   DeclinedThe issue was declined as something which matches the TypeScript visionThe issue was declined as something which matches the TypeScript vision

   SuggestionAn idea for TypeScriptAn idea for TypeScript

   on Feb 14, 2022
5. RyanCavanaugh commented on Feb 14, 2022

   

   Ryan Cavanaugh (RyanCavanaugh)

   on Feb 14, 2022

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   This doesn't come up often enough that we would "spend" syntax/complexity on it.
6. Ryan Cavanaugh (RyanCavanaugh)

   closed this as completedon Feb 14, 2022
7. RyanCavanaugh commented on Sep 24, 2025

   

   Ryan Cavanaugh (RyanCavanaugh)

   on Sep 24, 2025

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   Alternative you can use btw

   interface TupleOfLength<T> {
     0: [];
     1: [T];
     2: [T, T];
     3: [T, T, T];
     // Keep going as far as you have to (????)
   }
   
   // S = [string, string, string]
   type S = TupleOfLength<string>[3]

   I would recommend this over clever conditional type tricks because it's more performant and there's no reason you can't list out the longest tuple you'd realistically have