Evaluation of Expressions: Example 16/16
Example for a + b, where a.value = 10, b.value = 20
{Q2.s := Q2.i}
{Q1.s := Q2.s}
{E.s := Q1.s}
$
Parser pushdown:
Q2.i = 30
Semantic pushdown:
Input: $
Rule:
{Q1.s := Q2.s}
{E.s := Q1.s}
$
Q2.s = 30
43/69
E
10
+
20
T1
Q1
F2
R2
F1
R1
i1
e
e
e
T2
Q2
+
i2
Illustration:
+
{E.s := Q1.s}
$
Q1.s = 30
$
E.s = 30