Your bug report

#7161: 23.2; M-x highlight-phrase RET [[:space:]] RET --error--> Invalid regexp: "Invalid character class name"

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 7161@debbugs.gnu.org.

-- 
7161: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=7161
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