String concatenation vs Regex

JavaScript performance comparison

Revision 2 of this test case created

Info

This test compares performance of string interpolation using three techniqus: 1. String concatenation using addition operator. 2. Replace a part of string using regex 3. String concatenation using String.join() method.

Preparation code

 
<script>
Benchmark.prototype.setup = function() {
    var id = 1;
};
</script>

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Testing in unknown unknown
Test Ops/sec
String concatenation
var result = '[data-id="' + id + '"]';
pending…
Regex
var result = '[data-id="%d"]'.replace(/%d/, id);
pending…
String join
var result = ['[data-id="', id, '"]'].join('');
pending…
Concatenate using for loop
var items = ['[data-id="', id, '"]'],
    result = "",
    i = 0, l = items.length;
while (i < l) {
  result += items[i++];
}
pending…
var result = ['[data-id="', id, '"]'].reduce(function(prevValue, value) {
    return prevValue + value;
}, "");
pending…

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