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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
Suggestion
π Search Terms
generic, bind, call
β Viability 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, new syntax sugar for JS, etc.)
- This feature would agree with the rest of TypeScript's Design Goals.
β Suggestion
Currently, binding or calling a function loses its generics. Suggestion: Don't lose the generic.
π Motivating Example
Let's say I have a generic function getMediaAd
export async function getMediaAd<T extends Ad>(
this: Client,
params: { locale?: string; media_id: string; format: T['format'] },
) {
const url = this.cmsUrl(`api/ads/random`, params)
if (!params.locale) url.searchParams.set('locale', this.locale)
return this.get<T>(url, this.cmsHeaders())
}
This function can obtain multiple types of ad formats, determined by T
.
I want to put this function inside a Client class to access some client-specific features.
export class Client {
getMediaAd = getMediaAd.bind(this)
}
However, when I do that, this.getMediaAd
loses its generic parameter.
Losing the generic parameter means I can't tell it what is T
supposed to be, like this:
export async function getMediaBillboardAd(
this: Client,
params: { locale?: Intl.UnicodeBCP47LocaleIdentifier; media_id: string },
) {
return this.getMediaAd<AdBillboard>({ ...params, format: adFormat.billboard })
}
Here, T
is AdBillboard
. However, getMediaAd
expects 0 generic parameters.
π» Use Cases
I want to use this to create an API wrapper client, but keep the ability to declare functions in different files.
MadeBaruna, JesusTheHun, kermanx, stan-p, jonny133 and 7 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