Cleaned up BNF

qasm/parser.c

@@ -1,19 +1,44 @@
 // The following is an implementation of OpenQASM
 // using a recursive descent style parser.
 
-// MainProgram := "OPENQASM" Real ";" Program
-// Program ::= Statement | Program Statement
-// Statement ::= Decl 
-//             | GateDecl GeoList "}" 
-//             | GateDecl "}"
-//             | "opaque" Id Idlist ";"
-//             | "opaque" Id "()" IdList ";"
-//             | "opaque" Id "(" IdList ")" IdList ";"
-//             | Qop
-//             | "if" "(" Id "==" Integer ")" Qop
-//             | "barrier" AnyList ";"
-// Decl ::= "qreg" Id "[" Integer "]" ";" | "creg" Id "[" Integer "]" ";"
-// GateDecl ::= "gate" Id IdList "{" | "gate" Id "()" IdList "{" | "gate" Id "(" IdList ")" Idlist "{"
-// GopList ::= Uop | "barrier" IdList ";" | GopList Uop | GopList "barrier" IdList ";"
-// Qop ::= Uop | "measure" Argument "->" Argument ";" | "reset" Argument ";"
-// Uop ::= "U" "(" ExpList ")" Argument ";" | "CX" Argument "," Argument ";" | Id AnyList ";" | Id "()" AnyList ";" | Id ""
+// MainProgram ::= "OPENQASM" Real ";" Program
+//     Program ::= Statement | Program Statement
+//   Statement ::= Decl
+//               | GateDecl GeoList "}"
+//               | GateDecl "}"
+//               | "opaque" Id Idlist ";"
+//               | "opaque" Id "()" IdList ";"
+//               | "opaque" Id "(" IdList ")" IdList ";"
+//               | Qop
+//               | "if" "(" Id "==" Integer ")" Qop
+//               | "barrier" AnyList ";"
+//        Decl ::= "qreg" Id "[" Integer "]" ";"
+//               | "creg" Id "[" Integer "]" ";"
+//    GateDecl ::= "gate" Id IdList "{"
+//               | "gate" Id "()" IdList "{"
+//               | "gate" Id "(" IdList ")" Idlist "{"
+//     GopList ::= Uop
+//               | "barrier" IdList ";"
+//               | GopList Uop
+//               | GopList "barrier" IdList ";"
+//         Qop ::= Uop
+//               | "measure" Argument "->" Argument ";"
+//               | "reset" Argument ";"
+//         Uop ::= "U" "(" ExpList ")" Argument ";"
+//               | "CX" Argument "," Argument ";"
+//               | Id AnyList ";"
+//               | Id "()" AnyList ";"
+//               | Id "("  ExpList ")"  AnyList ";"
+//     AnyList ::= IdList | MixedList
+//      IdList ::= Id | IdList "," Id
+//   MixedList ::= Id "[" Integer "]"
+//               | MixedList "," Id
+//               | MixedList "," Id "[" Integer "]"
+//               | IdList "," Id "[" Integer "]"
+
+//    Argument ::= Id | Id "[" Integer "]"
+//     ExpList ::= Exp | ExpList "," Exp
+//         Exp ::= Real | Integer | "pi" | Id
+//               | Exp "+" Exp | Exp "-" Exp | Exp "*" Exp | Exp "/" Exp
+//               | "-" Exp | Exp "^" Exp | "(" Exp ")" | UnaryOp "(" Exp ")"
+//     UnaryOp ::= "sin" | "cos" | "tan" | "exp" | "ln" | "sqrt"