Infix to Postfix Directed by a BU Parser
11/69
Example:
Rule:
Semantic Action:
1
:
E
®
E
+
E
{
generate
(‘
+
’)
}
2
:
E
®
E
*
E
{
generate
(‘
*
’)
}
3
:
E
®
(
E
)
{ -
}
4
:
E
®
i
{
generate
(
i.
a
)
}
a
+
b
c
*
Input:
Output:
c
4
i
E
+
1
E
+
*
2
E
*
b
i
E
4
a
E
i
4
Gist: S
emantic actions produce the postfix version
of
the tokenized source program.