If you do so, the escape and the delimiter form part of the pattern, but since
delimiters are always non-alphanumeric, this does not affect its interpretation.
If the terminating delimiter is immediately followed by a backslash, for
example,
<pre>
  /abc/\
</pre>
then a backslash is added to the end of the pattern. This is done to provide a
way of testing the error condition that arises if a pattern finishes with a
backslash, because
<pre>
  /abc\/
</pre>
is interpreted as the first line of a pattern that s