For example, in the following grammar, with start symbol S0, S0 → AbB | C B → AA | AC C → b | c A → a | ε the nonterminal A, and hence also B, is nullable, while neither C nor S0 is. Hence the following intermediate grammar is obtained:indicating a kept and omitted nonterminal N by ' and ', respectively S0 → b | b | b | b | C B → ' | ' | ' | ε | C | C C → b | c A → a | ε In this grammar, all ε-rules have been "inlined at the call site".If the grammar had a rule S0 → ε, it could not be "inlined", since it had no "call sites". Therefore it could not be deleted in the next step. In the next step, they can hence be deleted, yielding the grammar: S0 → AbB | Ab | bB | b | C B → AA | A | AC | C C → b | c A → a This grammar produces the same language as the original example grammar, viz. {ab,aba,abaa,abab,abac,abb,abc,b,ba,baa,bab,bac,bb,bc,c}, but has no ε-rules.
For example, in the following grammar, with start symbol S0, S0 → AbB | C B → AA | AC C → b | c A → a | ε the nonterminal A and hence also B, is nullable, while neither C nor S0 is. Hence the following intermediate grammar is obtained:indicating a kept and omitted nonterminal N by ' and ', respectively S0 → b | b | b | b | C B → ' | ' | ' | ε | C | C C → b | c A → a | ε In this grammar, all ε-rules have been "inlined at the call site".If the grammar had a rule S0 → ε, it could not be "inlined" since it had no "call sites". Therefore it could not be deleted in the next step. In the next step, they can hence be deleted, yielding the grammar: S0 → AbB | Ab | bB | b | C B → AA | A | AC | C C → b | c A → a This grammar produces the same language as the original example grammar, viz. {ab,aba,abaa,abab,abac,abb,abc,b,ba,baa,babbac,bb,bc,c}, but has no ε-rules.