negate

Generate a result-negated version of a function.

function negate(x)
// x: a function

const xasyncfn = require('extra-async-function');


var fn = xasyncfn.negate(isFinite);
await fn(Infinity)
// → true
await fn(1)
// → false

var fn = xasyncfn.negate(isNaN);
await fn(1);
// → true
await fn(Promise.resolve(NaN));
// → false

References

• negate: Underscore.js documentation
• Learn You a Haskell for Great Good!: Higher order functions by Miran Lipovaca