<B>Tcl_GetRegExpFromObj</B> returns NULL and leaves an error message in
the interpreter result.  The regular expression token can be used as
long as the internal representation of <I>patObj</I> refers to the
compiled form.  The <I>cflags</I> argument is a bit-wise OR of
zero or more of the following flags that control the compilation of
<I>patObj</I>:
<P>
<DL class="description">
<DT><A NAME="M6"><B>TCL_REG_ADVANCED</B></A><DD>
Compile advanced regular expressions
(&#8220;ARE&#8221;s).
This mode corresponds