Checking that a Predicate is True for All Typescript Array Elements

Image by Jimmy Lau from Pixabay


We have an array of elements [1,2,'a'] , and we want to see whether all of the elements in the array are numbers.


This approach uses:

@fireflysemantics/validatorts to check whether the array element is a number:

let arr: any[] = [1, 2, 'a'];function allNumbersPredicate(v: any, index: number, array: any[]):boolean {
console.log(`is number ${isNumber(v).value}`);
return isNumber(v).value;
console.log(`All numbers:? ${arr.every(allNumbers)}`);


Founder of Firefly Semantics Corporation

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Ole Ersoy

Ole Ersoy

Founder of Firefly Semantics Corporation

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