⟨id⟩ ::= a | b | c | ... | z
⟨dig⟩ ::= 0 | 1 | 2 | ... | 9
⟨expr⟩ ::= () | ⟨dig⟩ | ⟨id⟩
| let ⟨id⟩ = ⟨expr⟩ in ⟨expr⟩
| ⟨expr⟩ ; ⟨expr⟩
| begin ⟨expr⟩ end
Demonstrate the grammar above is ambiguous.
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2. Modify the grammar (reproduced below) to be unambiguous. Hint: There is not just one way.
⟨id⟩ ::= a | b | c | ... | z
⟨dig⟩ ::= 0 | 1 | 2 | ... | 9
⟨expr⟩ ::= () | ⟨dig⟩ | ⟨id⟩
| let ⟨id⟩ = ⟨expr⟩ in ⟨expr⟩
| ⟨expr⟩ ; ⟨expr⟩
| begin ⟨expr⟩ end
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3. Demonstrate your modified grammar fixes the previously shown ambiguity.
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