Microsoft/TypeScript
Voir sur GitHubFunction expression or method is not inferable when we have mapped type with a conditional type
Open
#60 047 ouverte le 24 sept. 2024
Domain: check: Type InferenceHelp WantedPossible Improvement
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- Stars
- (48 455 stars)
- Métriques de merge PR
- (Merge moyen 6j 17h) (9 PRs mergées en 30 j)
Description
🔎 Search Terms
conditional method arrow function
🕗 Version & Regression Information
- This is the behavior in every version I tried, and I reviewed the FAQ
⏯ Playground Link
💻 Code
type Map<T> = {
readonly [P in keyof T]: T[P] extends boolean ? "boolean": "other"
}
export function buildCommand<F extends Record<string, unknown>>(builderArgs: {
func: (p: F) => void
params: Map<NoInfer<F>>
}) {
}
type Foo = { foo: boolean };
// Function expression does not work
buildCommand({
func: function (p: Foo) { },
params: {
foo: "boolean"
}
})
// Methods don't work
buildCommand({
func(p: Foo) { },
params: {
foo: "boolean"
}
})
// Arrow function works
buildCommand({
func: (p: Foo) => { },
params: {
foo: "boolean"
}
})
🙁 Actual behavior
For the first two calls we get an error while the third one is successful
🙂 Expected behavior
All three calls should be successful
Additional information about the issue
Removing the constraint from F (Playground Link) or changing it to F extends Record<keyof F, unknown> (Playground Link) will remove the error.