Question

Convert the following set of BNF rules to a single EBNF rule.

<E> --> <E> + <T>
     |  <E> - <T>
     |  <T>

Q2)   Briefly explain how the expected type and actual type of <expr>

            in the following two BNF rules are determined:

<assign> --> <var> = <expr>  (Rule 1)
<expr>   --> <var> + <var>   (Rule 2)

Answer 1

1)

2)