Chapter 4, Problem 4E

Explanation of Solution

S-attributed attribute grammar based on Context-Free-Grammar:

• The attribute grammar is developed based on Example 4.7.
• Here dynamic memory allocation is used to store the individual attributes which can hold small amount of information.
• The following grammar defines the S-attribute for the given situation.

$\begin{array}{l}\text{expr }\to \text{const expr tail }\Rightarrow \text{expr}\text{.v := reduce(const}\text{.v, expr tail}\text{.l)}\\ \text{expr tail }\to \text{- const expr tail}\Rightarrow {\text{expr tail}}_1\text{.1 := cons(const}{\text{.v, expr tail}}_2\end{array}$