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Awaiting More FeedbackThis means we'd like to hear from more people who would be helped by this featureThis means we'd like to hear from more people who would be helped by this featureSuggestionAn idea for TypeScriptAn idea for TypeScript
Description
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TemplateStringsArray, TaggedTemplateExpression
Suggestion
There shouldn't be a type TemplateStringsArray, it should be a const string tuple type, so we can write code:
interface SQL<TSA, VS> {
  texts: TSA;
  values: VS;
}
function sql<TSA extends readonly string[], VS extends any[]>(texts:TSA, ...values: VS): SQL<TSA, VS> {
  return { texts, values };
}
// then
let s: SQL<['select * from person where a=', ' and b=', ''], [number, Date]> = sql`select * from person where a=${1} and b=${new Date()}`;Use Cases
Just like in the above code, we can test the sql at compile time or use a TypeScript Language Service Plugin (in fact, I'm writing itts-sql-plugin and then come across this problem).
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Checklist
My suggestion meets these guidelines:
- This wouldn't be a breaking change in existing TypeScript/JavaScript code
 - This wouldn't change the runtime behavior of existing JavaScript code
 - This could be implemented without emitting different JS based on the types of the expressions
 - This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, etc.)
 - This feature would agree with the rest of TypeScript's Design Goals.
 
There is another issue is alike. #16552 (comment)
Besides, TemplateStringsArray is ReadonlyArray<string>, it should be const anyway.
flavin, elderapo, daniellwdb, klemens-morgenstern, thorn0 and 36 moreharrysolovay, a11delavar, maxpain, schickling and TylorSharrysolovay, a11delavar, sam-goodwin, nlepage, daisylb and 4 moreharrysolovay, a11delavar, sam-goodwin, timkendall, maxpain and 1 more
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Awaiting More FeedbackThis means we'd like to hear from more people who would be helped by this featureThis means we'd like to hear from more people who would be helped by this featureSuggestionAn idea for TypeScriptAn idea for TypeScript