ts-pattern/dist/types/ExtractPreciseValue.d.ts

The exhaustive Pattern Matching library for TypeScript.

import type { Override } from './Pattern.js';
import type { BuiltInObjects, Compute, Contains, IsPlainObject, IsReadonlyArray, LeastUpperBound, MaybeAddReadonly, ValueOf } from './helpers.js';
export type ExtractPreciseValue<a, b> = b extends Override<infer b1> ? b1 : unknown extends b ? a : 0 extends 1 & b ? a : 0 extends 1 & a ? b : b extends readonly any[] ? ExtractPreciseArrayValue<a, b, IsReadonlyArray<a>> : b extends Map<infer bk, infer bv> ? a extends Map<infer ak, infer av> ? Map<ExtractPreciseValue<ak, bk>, ExtractPreciseValue<av, bv>> : LeastUpperBound<a, b> : b extends Set<infer bv> ? a extends Set<infer av> ? Set<ExtractPreciseValue<av, bv>> : LeastUpperBound<a, b> : IsPlainObject<b, BuiltInObjects | Error> extends true ? a extends object ? a extends b ? a : b extends a ? Contains<b, never> extends true ? never : Contains<Omit<b, keyof a>, {}> extends true ? never : [
    Exclude<keyof a, keyof b>
] extends [never] ? b : Compute<b & Omit<a, keyof b>> : [keyof a & keyof b] extends [never] ? never : Compute<{
    [k in keyof a as k extends keyof b ? never : k]: a[k];
} & {
    [k in keyof b]: k extends keyof a ? ExtractPreciseValue<a[k], b[k]> : b[k];
}> extends infer result ? Contains<Pick<result, keyof result & keyof b>, never> extends true ? never : result : never : LeastUpperBound<a, b> : LeastUpperBound<a, b>;
type ExtractPreciseArrayValue<a, b, isReadonly extends boolean, startOutput extends any[] = [], endOutput extends any[] = []> = a extends readonly (infer aItem)[] ? b extends readonly [] ? MaybeAddReadonly<[...startOutput, ...endOutput], isReadonly> : b extends readonly [infer b1, ...infer bRest] ? a extends readonly [infer a1, ...infer aRest] ? ExtractPreciseValue<a1, b1> extends infer currentValue ? [currentValue] extends [never] ? never : ExtractPreciseArrayValue<aRest, bRest, isReadonly, [
    ...startOutput,
    currentValue
], endOutput> : never : ExtractPreciseValue<aItem, b1> extends infer currentValue ? [currentValue] extends [never] ? never : ExtractPreciseArrayValue<aItem[], bRest, isReadonly, [
    ...startOutput,
    currentValue
], endOutput> : never : b extends readonly [...infer bInit, infer b1] ? a extends readonly [...infer aInit, infer a1] ? ExtractPreciseValue<a1, b1> extends infer currentValue ? [currentValue] extends [never] ? never : ExtractPreciseArrayValue<aInit, bInit, isReadonly, startOutput, [
    ...endOutput,
    currentValue
]> : never : ExtractPreciseValue<aItem, b1> extends infer currentValue ? [currentValue] extends [never] ? never : ExtractPreciseArrayValue<aItem[], bInit, isReadonly, startOutput, [
    ...endOutput,
    currentValue
]> : never : ExtractPreciseValue<aItem, ValueOf<b>> extends infer currentValue ? [currentValue] extends [never] ? never : MaybeAddReadonly<[
    ...startOutput,
    ...currentValue[],
    ...endOutput
], isReadonly> : never : LeastUpperBound<a, b>;
export {};