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javascripttypescriptpiperamda.jsdrop

How to fix Ramda drop dropLast type error in pipe?

I am using below code using ramda in typescript and it keeps showing error that type is not matching:

R.pipe(R.drop(2), R.dropLast(5))("hello world");

TS2769: No overload matches this call.   The last overload gave the following error.     Argument of type '{ (xs: string): string; (xs: readonly unknown[]): unknown[]; }' is not assignable to parameter of type '(x0: readonly unknown[], x1: unknown, x2: unknown) => string'.       Types of parameters 'xs' and 'x0' are incompatible.         Type 'readonly unknown[]' is not assignable to type 'string'.

How should fix this?

Solution

  • It seems the type inference needs a bit of extra help to let it know that you want the type narrowed to a string.

    e.g.

    R.pipe<string, string, string>(R.drop(2), R.dropLast(5))("hello world")
// or
R.pipe(R.drop(2) as (str: string) => string, R.dropLast(5))("hello world")