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problem with metacharacter \b


Nati323
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in the reference http://www.w3schools.com/jsref/jsref_regexp_begin.asp, you say that b search for a word at the beginning and the end of a word, i try it but its not work on the end of a word, why is that?

the code:

    var str = "Visit W3SchoolsW3";     var patt1 = /(bW3)/g;    var result = str.match(patt1);    document.getElementById("demo").innerHTML = result;

And with a big B, its works but you say there that a big B search a match that is not at the start or end of a word:

var str = "Visit W3SchoolsW3";var patt1 = /BW3/g;var result = str.match(patt1);document.getElementById("demo").innerHTML=result;
Edited by Nati323
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My mistake on that last explanation, that wasn't correct.

i telling to regexp to search W3 at the end of the word

No, you're telling it to find a word boundary followed by W3. That will match at the beginning of a word, not the end. If you want to match the end then you need to look for W3 followed by a word boundary.
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A boundary is a border. The meaning of b isn't an actual character, it will actually match the position between the start or end of a word and a space character. Think of it like the cursor blinking when you type. When you put the cursor at the beginning or end of a word, that is the position that b will match. So bW will match a word that begins with W (the match will be just before the W), and Wb will match a word that ends with W (the match will be just after the W).

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