Normally a rule such as expr would be written in right-recursive style: expr: expression expr(?) So, the output always contains two productions but the second may be a recursive instance. Alsobear in mind this tool generates recursive descent compilers which do not know about niceties like operator precedence. So the definition of expr normally has to consist of other rules (such as term and factor) expressly to handle precedence. The author points out some differences between this and tools like yacc but there are many others.

In reply to Re: Can I get some rules help with PARSE::RECDESCENT by Anonymous Monk
in thread Can I get some rules help with PARSE::RECDESCENT by DevM

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