Ramda Negation In Both

Question

Why does the following fail to return a function?

const isValid = both(not(isEmpty), is(Object));

The item is valid if it:

1. Exists
2. Is an Array
3. Is not empty

Answer 1

As mentioned in my comment, not is, ahem, not what you want. Instead, try complement:

const isValid = R.both(R.complement(R.isEmpty), R.is(Array));
console.log(isValid);
console.log(isValid([1,2,3]));

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