code: function subst(str, file, dst) {
              if (dst !== undefined) {
                  str = str.replace(/\{\{DST\}\}/g, dst);
              }
              var dir = path.dirname(file);
              str = str.replace(/\{\{SRC\}\}/g, file);
              var name = path.basename(file);
              str = str.replace(/\{\{NAME\}\}/g, name);
              name = name.replace(/\.\w+$/, '');
              str = str.replace(/\{\{BASENAME\}\}/g, name);
              str = str.replace(/\{\{DIR\}\}/g, dir);
              var parts =     dir.split(path.sep);
              parts.splice(0, 1);
              str = str.replace(/\{\{SUBDIR\}\}/g, path.join.apply(null, parts));
              parts.splice(0, 1);
              str = str.replace(/\{\{SUBSUBDIR\}\}/g, path.join.apply(null, parts));
              return str;
          }
docs: Support function to substitute path variables.