This man page describes the regular expression syntax supported within Tcl.
http://www.purl.org/tcl/home/man/tcl8.4/TclCmd/re_syntax.htm
If someone were so inclined, it would be useful to add, to this page, some examples of how to use some of the more complex regular expression syntax functions.
For instance:
Many threads in the comp.lang.tcl newsgroup have inspired wonderful instances of RE explication. Michael A. Cleverly, for example, wrote a delightful one [L1 ] on "Extracting numbers from text strings, removing unwanted characters".
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