locutus
Version:
Locutus other languages' standard libraries to JavaScript for fun and educational purposes
28 lines (27 loc) • 970 B
JavaScript
export function is_finite(val) {
// discuss at: https://locutus.io/php/is_finite/
// original by: Onno Marsman (https://twitter.com/onnomarsman)
// example 1: is_finite(Infinity)
// returns 1: false
// example 2: is_finite(-Infinity)
// returns 2: false
// example 3: is_finite(0)
// returns 3: true
let warningType = '';
if (val === Infinity || val === -Infinity) {
return false;
}
// Some warnings for maximum PHP compatibility
if (typeof val === 'object') {
warningType = Array.isArray(val) ? 'array' : 'object';
}
else if (typeof val === 'string' && !/^[+-]?\d/.test(val)) {
// simulate PHP's behaviour: '-9a' doesn't give a warning, but 'a9' does.
warningType = 'string';
}
if (warningType) {
const msg = 'Warning: is_finite() expects parameter 1 to be double, ' + warningType + ' given';
throw new Error(msg);
}
return true;
}