Part 12: Fix declarations grammar

holyketzer · Feb 6, 2021 · b9111d7 · b9111d7
1 parent 69fbdea
commit b9111d7
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Showing 2 changed files with 32 additions and 5 deletions.
diff --git a/interpreter.py b/interpreter.py
@@ -42,9 +42,11 @@
 #    | declarations compound_statement
 
 # declarations:
-#    | VAR (variable_declaration SEMI)+ (procedure_declaration)*
-#    | (procedure_declaration)*
-#    | empty
+#    | (declaration)*
+
+# declaration:
+#    | VAR (variable_declaration SEMI)+
+#    | (procedure_declaration)+
 
 # procedure_declaration:
 #    | PROCEDURE ID SEMI block SEMI
@@ -385,14 +387,24 @@ def block(self):
 
     def declarations(self):
         res = []
+
+        declaration = self.declaration()
+        while declaration:
+            res += declaration
+            declaration = self.declaration()
+
+        return res
+
+    def declaration(self):
+        res = []
+
         if self.current_token.type == VAR:
             self.eat(VAR)
 
             while self.current_token.type == ID:
                 res += self.variable_declaration()
                 self.eat(SEMI)
-
-        while self.current_token.type == PROCEDURE:
+        elif self.current_token.type == PROCEDURE:
             res.append(self.procedure_declaration())
 
         return res

diff --git a/test.pas b/test.pas
@@ -4,6 +4,21 @@
    a, b   : INTEGER;
    y      : REAL;
 
+PROCEDURE p1;
+   var x : INTEGER;
+begin
+   x := 1;
+end;
+
+VAR
+   nnn : INTEGER;
+
+PROCEDURE p2;
+   var x2 : INTEGER;
+begin
+   x2 := 1;
+end;
+
 BEGIN {Part11}
    number := 2;
    a := number ;