`` で使いまわせるテンプレート

template.js

Array.prototype.alternate = function(...arrs){
    var res = []
    arrs.unshift(this)
    for(var i=0, precount=-1;precount!==(precount=res.length);i++){
        for(var j=0;j<arrs.length;j++){
            var arr = arrs[j]
            i < arr.length && res.push(arr[i])
        }
    }
    return res
}

function Template(parts, ...names){
    var obj = {
         parts,
         names
    }
    obj.__proto__ = Template.prototype
    return obj
}
Template.prototype.generate = function(elements){
    if(Array.isArray(elements)){
        return this.parts.alternate(elements.slice(0, this.names.length)).join("")
    }else{
        return this.parts.alternate(this.names.map(e => elements[e])).join("")
    }
}

usage.js

var template = Template `(${"test"}) [${"sample"}] "${"name"}"`
var result = template.generate({
    test: "てすと",
    sample: "さんぷる",
    name: "なまえ"
})
console.log(result)
// (てすと) [さんぷる] "なまえ"

var result = template.generate([123,456,7890])
console.log(result)
// (123) [456] "7890"