String concatenation (many small strings) (v6)

Revision 6 of this benchmark created by Roy Tinker on

Description

Testing string concatenation methods in straight code and abstracted in a StringBuilder.

Preparation HTML

<script>

window.CONST = {
    STR_PART: function(i) {
      return String.fromCharCode(i);
    },
    ITERATIONS: 20000
  };

function StringBuilderConcat() {
  this._str = "";
}

StringBuilderConcat.prototype.append = function (str) {
    this._str += str;
}

StringBuilderConcat.prototype.toString = function () {
  return this._str;
}

function StringBuilderArrayPush() {
    this._array = [];
}

StringBuilderArrayPush.prototype.append = function (str) {
    this._array.push(str);
}

StringBuilderArrayPush.prototype.toString = function () {
  return this._array.join('');
}

function StringBuilderArrayIndex() {
  this._array = [];
  this._index = 0;
}

StringBuilderArrayIndex.prototype.append = function (str) {
    this._array[this._index] = str;
    this._index++;
}

StringBuilderArrayIndex.prototype.toString = function () {
  return this._array.join('');
}
</script>

Test runner

Ready to run.

Testing in
TestOps/sec
Array index - No Abstraction
var build = [];
for (var i = 0; i < CONST.ITERATIONS; i++) {
  build[i] = CONST.STR_PART(i);
}
var out = build.join('');
ready
Array push - No abstraction
var build = [];
for (var i = 0; i < CONST.ITERATIONS; i++) {
  build.push(CONST.STR_PART(i));
}

var out = build.join('');
ready
Straight String Concat - No abstraction
var build = "";
for (var i = 0; i < CONST.ITERATIONS; i++) {
  build += CONST.STR_PART(i);
}
ready
StringBuilder - Array index
var builder = new StringBuilderArrayIndex();
for (var i = 0; i < CONST.ITERATIONS; i++) {
  builder.append(CONST.STR_PART(i));
}
var out = builder.toString();
ready
StringBuilder - Array push
var builder = new StringBuilderArrayPush();
for (var i = 0; i < CONST.ITERATIONS; i++) {
  builder.append(CONST.STR_PART(i));
}
var out = builder.toString();
ready
StringBuilder - string concat
var builder = new StringBuilderConcat();
for (var i = 0; i < CONST.ITERATIONS; i++) {
  builder.append(CONST.STR_PART(i));
}
var out = builder.toString();
ready

Revisions

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