introduction to web programming Anchors Regular expressions also take advantage of anchoring patterns that help match the string in relationship to the rest of the line. For example, the "\b" anchor is used to specify a word boundary. That is, "/\beric\b/" matches "eric", but it does not match "generic".

Similarly, the caret (^) anchor will match a string to the beginning of the line. Thus, "/^eric/" will match the following line

     eric is my name

but it will not match

     my name is eric

Warning: the caret (^) can be confusing since it is used as an anchor when included "outside" of the square brackets ([]) but is used as the "not" operator for a class when used "within".
The following table summarizes a few of the most common anchors.

Anchor Description
^ Matches the beginning of the string
$ Matches the end of the string
\b Matches a word boundary (between \w and \W)
\B Matches on non-word boundary

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