Evaluation of Expressions: Example 6/16
Example for a + b, where a.value = 10, b.value = 20
{R1.i := F1.s}
R1
{T1.s := R1.s}
{Q1.i := T1.s}
Q1
{E.s := Q1.s}
$
Parser pushdown:
F1.s = 10
Semantic pushdown:
Input: + i2 $
Rule:
33/69
E
10
+
20
T1
Q1
F1
R1
i1
Illustration:
R1
{T1.s := R1.s}
{Q1.i := T1.s}
Q1
{E.s := Q1.s}
$
R1.i = 10
R1 ® e {R1.s := R1.i}