e>/</code>. 
The delimiter may be quoted in <var>old</var> and <var>new</var>
with a single backslash.  If <code>&amp;</code> appears in <var>new</var>,
it is replaced by <var>old</var>.  A single backslash will quote
the <code>&amp;</code>.  The final delimiter is optional if it is the last
character on the input line.

     <br><dt><code>&amp;</code>
     <dd>Repeat the previous substitution.

     <br><dt><code>g</code>
     <dd><dt><code>a</code>
     <dd>Cause changes to be applied over the entire even