We consider rewriting systems based on production rules of the form $u\to v$, where $u$ and $v$ are patterns. Using such a rule means to find in the string to be rewritten a substring $x$ which matches with the pattern $u$ and to replace it with a string obtained by "interpreting" $v$ according to the restrictions imposed by the matching of $u$ with $x$. Free, maximal, and minimal use of left-hand patterns are considered. The generative capacity of the obtained grammars is investigated. A series of directions for further research are also mentioned.

Journal of Automata, Languages and Combinatorics, Volume 1, Number 3, 1996, 219-235