conditioned regex_replace

bundle edit_line regex_replace_cond(find,replace)
{
vars:

        "ereplace"              string => escape("$(replace)");

classes:

        "patched"       expression => regline(  ".*$(ereplace).*",
                                                "$(edit.filename)"
                                                );
replace_patterns:

    !patched::

        "(?!$(ereplace))$(find)"
                replace_with    => value("$(replace)"),
                comment         => "Search and replace string conditional";

}