Update oc.py example: fix regex for '==' operator, add packrat parsing and function call as expression operand

1 files changed, 6 insertions, 4 deletions

diff --git a/src/examples/oc.py b/src/examples/oc.py
index 42b9d48..cf656ec 100644
--- a/src/examples/oc.py
+++ b/src/examples/oc.py
@@ -71,6 +71,7 @@ The following is a description of the OC grammar:
 """

 

 from pyparsing import *

+ParserElement.enablePackrat()

 

 LPAR,RPAR,LBRACK,RBRACK,LBRACE,RBRACE,SEMI,COMMA = map(Suppress, "()[]{};,")

 INT, CHAR, WHILE, DO, IF, ELSE, RETURN = map(Keyword, 

@@ -82,10 +83,10 @@ char = Regex(r"'.'")
 string_ = dblQuotedString

 

 TYPE = Group((INT | CHAR) + ZeroOrMore("*"))

-

 expr = Forward()

-operand = NAME | integer | char | string_

-expr << (infixNotation(operand, 

+func_call = Group(NAME + LPAR + Group(Optional(delimitedList(expr))) + RPAR)

+operand = func_call | NAME | integer | char | string_

+expr <<= (infixNotation(operand, 

     [

     (oneOf('! - *'), 1, opAssoc.RIGHT),

     (oneOf('++ --'), 1, opAssoc.RIGHT),

@@ -93,7 +94,7 @@ expr << (infixNotation(operand,
     (oneOf('* / %'), 2, opAssoc.LEFT),

     (oneOf('+ -'), 2, opAssoc.LEFT),

     (oneOf('< == > <= >= !='), 2, opAssoc.LEFT),

-    (Regex(r'=[^=]'), 2, opAssoc.LEFT),

+    (Regex(r'(?<!=)=(?!=)'), 2, opAssoc.LEFT),

     ]) + 

     Optional( LBRACK + expr + RBRACK | 

               LPAR + Group(Optional(delimitedList(expr))) + RPAR )

@@ -176,6 +177,7 @@ main()
 {

     int i;

     i = 0;

+    if(a() == 1){}

     while(i < 10)

         facpr(i++);

     return 0;