Position Anchors
We'll leave character classes aside for a while, and look at the difference between matching characters and positions. There are times when we want to match a pattern only if it is at a certain place, relative to line or word boundaries.
Line boundaries are specified by the caret (^) and dollar sign ($) characters; these represent the start and end of a line, respectively. So /^Fre/ matches "Freedom's just another word" but not "Cooking with Freya". To make sure what you match is on a line by itself, use both, as in /^INTRODUCTION:$/.
Line boundary matching respects the divisions within a multiline string.
rhyme = "Mary Mary\nQuite contrary" /ary/ =~ rhyme #-> 1 /ary$/ =~ rhyme #-> 6 /rary$/ =~ rhyme #-> 20
Ruby also recognizes ...
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