Function isMatching

isMatching<const p extends UnknownPattern>(
    pattern: p,
): (value: unknown) => value is InvertPattern<NoInfer<p>, unknown>

const hasName = isMatching({ name: P.string })

 declare let input: unknown

 if (hasName(input)) {
   // `input` inferred as { name: string }
   return input.name
 }
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isMatching<
    const T,
    const P extends
    
            | undefined
            | null
            | string
            | number
            | bigint
            | boolean
            | symbol
            | readonly []
            | readonly [unknown, unknown]
            | readonly [unknown, unknown]
            | UnknownProperties
            | UnknownMatcher
            | PatternMatcher<T<T>>
            | string & readonly any[]
            | number & readonly any[]
            | bigint & readonly any[]
            | false & readonly any[]
            | true & readonly any[]
            | symbol & readonly any[]
            | {
                readonly [k in string | number | symbol]?: Pattern.Pattern<
                    Readonly<
                        MergeUnion<
                            Exclude<
                                T<T>,
                                readonly any[] | Primitives | Map<any, any> | Set<any>,
                            >,
                        >,
                    >[k],
                >
            }
            | readonly UnknownPattern[]
            | readonly [UnknownPattern, UnknownPattern]
            | readonly [UnknownPattern, UnknownPattern]
            | PatternMatcher<T>
            | {
                readonly [k in string | number | symbol]?: Pattern.Pattern<
                    Readonly<
                        MergeUnion<
                            Exclude<T, readonly any[] | Primitives | Map<any, any> | Set<any>>,
                        >,
                    >[k],
                >
            },
>(
    pattern: P,
    value: T,
): value is InvertPattern<NoInfer<P>, unknown>

declare let input: unknown

 if (isMatching({ name: P.string }, input)) {
   // `input` inferred as { name: string }
   return input.name
 }
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