premap

import { premap } from "https://raw.githubusercontent.com/baetheus/fun/main/predicate.ts";

Create a Predicate using a Predicate and a function that takes a type L and returns a type D. This maps over the input value of the predicate.

@example

import { premap } from "./predicate.ts";
import { pipe } from "./fn.ts";

const isGreaterThan3 = (n: number) => n > 3;
const isLongerThan3 = pipe(
  isGreaterThan3,
  premap((s: string) => s.length),
);

const result1 = isLongerThan3("Hello"); // true
const result2 = isLongerThan3("Hi"); // false

function premap<I, A>(fia: (i: I) => A): (ua: Predicate<A>) => Predicate<I>;

premap<I, A>(fia: (i: I) => A): (ua: Predicate<A>) => Predicate<I>

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§Type Parameters

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§Parameters

fia: (i: I) => A

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§Return Type

(ua: Predicate<A>) => Predicate<I>

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