Regular expressions are used for matching text with a pattern. The
transformation obfuscates regular expression literals to make them harder to
understand by a human without changing their original pattern.
The regular expression becomes harder to read because each character and
special-character (e.g., character classes, character sets, quantifiers) is
replaced with a more verbose (but equivalent) representation.
Also the same regular expression will look different each time you obfuscate
it because the character replacements are randomly generated, making the
obfuscated output look polymorphic.
Consider the following regular expression to match old IE user agents:
The transformation produces random results so the following example is a possible