This instruction has the syntax
prod NONT_QUOTED, RHS
The instruction increments the frequency of a production from a context-free grammar for a regular expression and updates the spur accordingly. The production has a nonterminal symbol NONT_QUOTED specified in double quotation marks at the left-hand side and a right-hand side with zero-based index RHS.
prod "B", 4
This instruction increments the frequency of a production with the nonterminal symbol
B at the left-hand side and the fifth right-hand side for that nonterminal symbol.