Perl 6 Deep Dive

Matching at the start and at the end of lines or strings

Let us modify the phone number regex so that it forces the regex to match with the whole string containing a potential phone number:

/ ^ \+? <[\d\s\-]>+ $ /;

Here, ^ is the anchor that matches at the beginning of the string and does not consume any characters. On the other side of the regex, $ requires that the end of the regex matches the end of the string. So, a valid phone number, say [phone] will pass the filter, while a mathematical expression such as 124 + 35 - 36 will not.

For better visibility, anchors can be written on separate lines in the code:

my $rx = /    ^        \+?        <[\d\s\-]>+    $/;say 'OK'     if '[phone]' ~~ $rx; # OKsay 'Not OK' if '124 + 35 - 36' !~~ $rx; # Not ...