65 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			TypeScript
		
	
	
	
	
	
			
		
		
	
	
			65 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			TypeScript
		
	
	
	
	
	
| type RemoveFromTuple<
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|   Tuple extends readonly unknown[],
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|   RemoveCount extends number,
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|   Index extends 1[] = []
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| > = Index["length"] extends RemoveCount
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|   ? Tuple
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|   : Tuple extends [infer First, ...infer Rest]
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|   ? RemoveFromTuple<Rest, RemoveCount, [...Index, 1]>
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|   : Tuple;
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| 
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| type ConcatTuples<
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|   Prefix extends readonly unknown[],
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|   Suffix extends readonly unknown[]
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| > = [...Prefix, ...Suffix];
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| 
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| type ExtractFunctionParams<T> = T extends (this: infer TThis, ...args: infer P extends readonly unknown[]) => infer R
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|   ? { thisArg: TThis; params: P; returnType: R }
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|   : never;
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| 
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| type BindFunction<
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|   T extends (this: any, ...args: any[]) => any,
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|   TThis,
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|   TBoundArgs extends readonly unknown[],
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|   ReceiverBound extends boolean
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| > = ExtractFunctionParams<T> extends {
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|   thisArg: infer OrigThis;
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|   params: infer P extends readonly unknown[];
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|   returnType: infer R;
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| }
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|   ? ReceiverBound extends true
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|     ? (...args: RemoveFromTuple<P, Extract<TBoundArgs["length"], number>>) => R extends [OrigThis, ...infer Rest]
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|       ? [TThis, ...Rest] // Replace `this` with `thisArg`
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|       : R
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|     : <U, RemainingArgs extends RemoveFromTuple<P, Extract<TBoundArgs["length"], number>>>(
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|         thisArg: U,
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|         ...args: RemainingArgs
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|       ) => R extends [OrigThis, ...infer Rest]
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|       ? [U, ...ConcatTuples<TBoundArgs, Rest>] // Preserve bound args in return type
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|       : R
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|   : never;
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| 
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| declare function callBind<
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|   const T extends (this: any, ...args: any[]) => any,
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|   Extracted extends ExtractFunctionParams<T>,
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|   const TBoundArgs extends Partial<Extracted["params"]> & readonly unknown[],
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|   const TThis extends Extracted["thisArg"]
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| >(
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|   args: [fn: T, thisArg: TThis, ...boundArgs: TBoundArgs]
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| ): BindFunction<T, TThis, TBoundArgs, true>;
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| 
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| declare function callBind<
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|   const T extends (this: any, ...args: any[]) => any,
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|   Extracted extends ExtractFunctionParams<T>,
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|   const TBoundArgs extends Partial<Extracted["params"]> & readonly unknown[]
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| >(
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|   args: [fn: T, ...boundArgs: TBoundArgs]
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| ): BindFunction<T, Extracted["thisArg"], TBoundArgs, false>;
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| 
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| declare function callBind<const TArgs extends readonly unknown[]>(
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|   args: [fn: Exclude<TArgs[0], Function>, ...rest: TArgs]
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| ): never;
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| 
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| // export as namespace callBind;
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| export = callBind;
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