ben@Tyr:~$ perl -we'@list = 1..24; print "'4' found at \$list[$_]\n" f
+or grep { $list[$_] =~ /4/ } 0 .. $#list'
4 found at $list[3]
4 found at $list[13]
4 found at $list[23]
ben@Tyr:~$ perl -we'@list = 1..24; print "'4' found at \$list[$_]\n" f
+or grep { $list[$_] =~ /^4$/ } 0 .. $#list'
4 found at $list[3]
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The first example matches '4' anywhere in the element; the second one is a precise match.

-- 
Human history becomes more and more a race between education and catastrophe. -- HG Wells