grep
grep - locate elements in a list test true against a given criterion
grep BLOCK LIST
grep EXPR,LIST
Evaluates the BLOCK or EXPR for each element of LIST (locally setting
$_
to each element) and returns the list value consisting of those
elements for which the expression evaluated to TRUE. In a scalar
context, returns the number of times the expression was TRUE.
<![CDATA[
@foo = grep(!/^#/, @bar); # weed out comments
]]>
or equivalently,
<![CDATA[
@foo = grep {!/^#/} @bar; # weed out comments
]]>
Note that, since
$_
is a reference into the list value, it can be used
to modify the elements of the array. While this is useful and
supported, it can cause bizarre results if the LIST is not a named
array.