Modify the attribute grammar of Example 3.6 in Sebesta so that it uses only a single (synthesized) attribute.

An Attribute Grammar for Simple Assignment Statements 1. Syntax rule: = Semantic rule: .expected_type .actual_type 2. Syntax rule: [2] + [3] Semantic rule: .actual_type if ([2].actual_type = int) and ([3].actual_type = int) then int else real end if Predicate: .actual_type == .expected_type 3. Syntax rule: Semantic rule: .actual_type .actual_type Predicate: .actual_type == .expected_type 4. Syntax rule: A | B | C Semantic rule: .actual_type look- up(< var>.string) The look- up function looks up a given variable name in the symbol table and returns the variables type.