JSFiddle - React, Tailwind, and code Playground

JavaScript

var str=new Array();
str[0]='usemtl ftw';
str[1]='kd 1.2 3.2 3.1';
str[2]='v  -12.1892 -53.4267 -276.4055';

var r=/^(\w+) +(([\S]+)( [\S]+)*) *$/;

for(var i=0;i<str.length;i++)
{
    document.write('String '+i+': '+r.test(str[i])+'<br>');
}