Definition
A regular tree grammar is defined by the tuple
,
where
- is a set of nonterminals,
- is a ranked alphabet (i.e., an alphabet whose symbols have an associated arity) disjoint from ,
- is the starting nonterminal, with, and
- is a set of productions of the form, where, and, where is the associated term algebra, i.e. the set of all trees composed from symbols in according to their arities, where nonterminals are considered nullary.
Read more about this topic: Regular Tree Grammar
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