Regular Expressions 101

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"
^(?!highspeed)(?!regular).*$
"
gm
^ asserts position at start of a line
Negative Lookahead
(?!highspeed)
Assert that the Regex below does not match
highspeed
matches the characters highspeed literally (case sensitive)
Negative Lookahead
(?!regular)
Assert that the Regex below does not match
regular
matches the characters regular literally (case sensitive)
.
matches any character (except for line terminators)
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
$ asserts position at the end of a line
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.

Regular Expression
No Match

r"
"
gm

Test String

Code Generator

Generated Code

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Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report.
For a full regex reference for Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html