const template = {
    "Classes": {
        "_string": "Unit Organic ConquestCritical Human CitizenSoldier"
    },
    "VisibleClasses": {
        "_string": "Citizen Worker Soldier Infantry Ranged Archer"
    },
    "Rank": "Basic"
};

const iterations = 10000000;

function GetIdentityClasses1(template) {
    var classList = [];
    if (template.Classes && template.Classes._string)
        classList = classList.concat(template.Classes._string.split(/\s+/));

    if (template.VisibleClasses && template.VisibleClasses._string)
        classList = classList.concat(template.VisibleClasses._string.split(/\s+/));

    if (template.Rank)
        classList = classList.concat(template.Rank);

    return classList;
};

function GetIdentityClasses2(template) {
    var classList = [];
    if (template.Classes && template.Classes._string)
        classList = classList.concat(template.Classes._string.split(/\s+/));

    if (template.VisibleClasses && template.VisibleClasses._string)
        classList = classList.concat(template.VisibleClasses._string.split(/\s+/));

    if (template.Rank)
        classList = classList.push(template.Rank);

    return classList;
};

function GetIdentityClasses3(template)
{
	let classString = "";

	if (template.Classes && template.Classes._string)
		classString += template.Classes._string;

	if (template.VisibleClasses && template.VisibleClasses._string)
		classString += template.VisibleClasses._string;

	if (template.Rank)
		classString += " " + template.Rank;

	return classString.length ? classString.split(/\s+/) : [];
};

function GetIdentityClasses4(template) {
    let classString = "";

    if (template.Classes && template.Classes._string)
        classString += template.Classes._string;

    if (template.VisibleClasses && template.VisibleClasses._string)
        classString += template.VisibleClasses._string;

    if (template.Rank)
        classString += " " + template.Rank;

	return classString.length ? classString.split(/\s+/) : [];
};
let start = process.hrtime()[0];
for(let a = 0; a < iterations; ++a)
    GetIdentityClasses1(template);

let duration = process.hrtime()[0] - start;
console.log(duration / iterations * 1000 + " ms.");

start = process.hrtime()[0];
for(let a = 0; a < iterations; ++a)
    GetIdentityClasses2(template);

duration = process.hrtime()[0] - start;
console.log(duration / iterations * 1000 + " ms.");


start = process.hrtime()[0];
for(let a = 0; a < iterations; ++a)
    GetIdentityClasses3(template);

duration = process.hrtime()[0] - start;
console.log(duration / iterations * 1000 + " ms.");


start = process.hrtime()[0];
for(let a = 0; a < iterations; ++a)
    GetIdentityClasses4(template);

duration = process.hrtime()[0] - start;
console.log(duration / iterations * 1000 + " ms.");