SYNTAX            : RANGE @R / STRING 1 / STRING 2 /
                  : RANGE @R / / STRING 2 /

RESULTING ARGUMENT: Number of changes

FUNCTION          : Replace a character string by another character string
                    as many times as possible within the range. After
                    execution, the cursor (and implicitly the value of  . )
                    is positioned immediately after the last string replaced.
                    It is not necessary to position the cursor within the
                    range; it is automatically moved to the beginning of the
                    range before the search starts.

                    The modification character (delimiter) immediately
                    follows the command in the command sequence. This
                    character will be used instead of the ESC in the normal
                    replace command. This character is followed by the
                    first string, which is terminated by the modification
                    character. The second string follows, which is in turn
                    terminated by another identical modification character.

                    No error-condition will ever result; the number of
                    matches (whether 0 or higher) is simply returned.

RANGE             : START,END
                    START         : the buffer position to start at
                    END           : the buffer position to stop at

EXAMPLE           : h @r / hello ESC / world / =
                    Will replace the string hello ESC by world  as many
                    times as possible, and show the number of replacements.

NOTE 1            : Search-behaviour is governed by the Search Mode setting
                    (see CTRL_X)

NOTE 2            : If the first string is empty (as in h @r / / world /)
                    then the previous search string is reused.

NOTE 3            : The search string (used for both search and replace
                    commands) is accessable in register _ at all times.

NOTE 4            : The modification character is arbitrary. It must not
                    occur in either search- or replacement string.

NOTE 5            : The RETURN character is allowed anywhere in the search-
                    or replacement string.

MATRIX