Description
Describe the bug
// Define a type alias for variadic functions
type PipeFunctions = [(source: Observable) => any, ...Array<UnaryFunction<any, any>>];
class Observable {
// Simplified pipe method using variadic tuple types
pipe(...operations: PipeFunctions): R {
return _pipe(...operations)(this as any);
}
}
Explanation:
Type Alias for Variadic Functions:
PipeFunctions is a tuple type
- where the first element is a function that takes an Observable and
returns any, - followed by any number of UnaryFunction<any, any>.
Generic Pipe Method:
The pipe method is defined with a single generic parameter R to infer the return type based on the provided operations.
The method accepts a rest parameter ...operations typed as PipeFunctions.
Using _pipe Function:
Within the pipe method, the operations are passed to the _pipe function using the spread operator ...operations.
The result of _pipe(...operations) is then called with this (the current Observable instance), which effectively chains the operations together.
This approach significantly reduces the number of overload signatures required and leverages TypeScript's variadic tuple types to handle any number of operations in a type-safe manner.
Expected behavior
// Define a type alias for variadic functions
type PipeFunctions = [(source: Observable) => any, ...Array<UnaryFunction<any, any>>];
class Observable {
// Simplified pipe method using variadic tuple types
pipe(...operations: PipeFunctions): R {
return _pipe(...operations)(this as any);
}
}
Explanation:
Type Alias for Variadic Functions:
PipeFunctions is a tuple type
- where the first element is a function that takes an Observable and
returns any, - followed by any number of UnaryFunction<any, any>.
Generic Pipe Method:
The pipe method is defined with a single generic parameter R to infer the return type based on the provided operations.
The method accepts a rest parameter ...operations typed as PipeFunctions.
Using _pipe Function:
Within the pipe method, the operations are passed to the _pipe function using the spread operator ...operations.
The result of _pipe(...operations) is then called with this (the current Observable instance), which effectively chains the operations together.
This approach significantly reduces the number of overload signatures required and leverages TypeScript's variadic tuple types to handle any number of operations in a type-safe manner.
Reproduction code
// Define a type alias for variadic functions
type PipeFunctions<T> = [(source: Observable<T>) => any, ...Array<UnaryFunction<any, any>>];
class Observable<T> {
// Simplified pipe method using variadic tuple types
pipe<R>(...operations: PipeFunctions<T>): R {
return _pipe(...operations)(this as any);
}
}
------------------------
Explanation:
Type Alias for Variadic Functions:
PipeFunctions<T> is a tuple type
- where the first element is a function that takes an Observable<T> and
returns any,
- followed by any number of UnaryFunction<any, any>.
Generic Pipe Method:
The pipe method is defined with a single generic parameter R to infer the return type based on the provided operations.
The method accepts a rest parameter ...operations typed as PipeFunctions<T>.
Using _pipe Function:
Within the pipe method, the operations are passed to the _pipe function using the spread operator ...operations.
The result of _pipe(...operations) is then called with this (the current Observable instance), which effectively chains the operations together.
This approach significantly reduces the number of overload signatures required and leverages TypeScript's variadic tuple types to handle any number of operations in a type-safe manner.Reproduction URL
No response
Version
whatever
Environment
yes
Additional context
yes