Parsing email addresses out of text is far from trivial. *Any* ASCII character can be part of an email address, including NUL characters, white space and control characters. Here are some examples of valid email addresses:

*@example.net
"\""@foo.bar
fred&barny@example.com
---@example.com                                  
foo-bar@example.net
"127.0.0.1"@[127.0.0.1]
Muhammed.(I am  the greatest) Ali @(the)Vegas.WBA
':;
$@[]
*()@[]
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As for the general question, "how do I store all strings that a regex matches", just use the regex in list context, with a /g modifier. If you have capturing parens in your regex, you'll have to put a set of parens around the whole regex, and filter out the submatches (but it's probably easier to turn the capturing parens into non-capturing).

Abigail