Info

Tests the performance difference of using two different ways of concatenating strings. The two TCs produce the same string result.

See http://jsperf.com/forloop-vs-reverse-while-loop-and-array-reverse/9 for array reverse vs custom loops.

See http://jsperf.com/array-push-reverse-vs-unshift-reverse for array push reverse vs. unshift reverse.

Preparation code

<script>
  var length = 1500;
  var html = [];
  var str = "";
</script>

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str = "";
while (str.length < length) {
  str += '0';
}

str = "";
while (html.length < length) {
  html.push('0');
}
str = html.join("");

str = "";
while (html.length < length) {
  html.unshift('0');
}
str = html.join("");

str = "";
while (html.length < length) {
  html.push('0');
}
html.reverse();
str = html.join("");

str = "";
while (html.length < length) {
  html.unshift('0');
}
html.reverse();
str = html.join("");

str = "";
while (html.length < length) {
  html[html.length] = "0";
}
str = html.join("");

str = "";
while (html.length < length) {
  html[html.length] = "0";
}
html.reverse();
str = html.join("");

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Revisions

You can edit these tests or add even more tests to this page by appending /edit to the URL. Here’s a list of current revisions for this page:

• Revision 1: published by FredCK on 10th June 2011
• Revision 2: published on 6th July 2011
• Revision 3: published on 9th July 2011
• Revision 5: published on 15th September 2011
• Revision 6: published by XP1 on 2nd February 2012
• Revision 7: published on 3rd February 2012
• Revision 8: published on 13th February 2012
• Revision 9: published on 12th April 2012

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