added <> as inequality operator

Author: timmi-on-rails

ExpressionTest/TokenizerTest.cs

@@ -14,6 +14,7 @@ public void TestEveryTokenType()
 			AssertTokensMatch("=", Token(TokenType.Assignment, "=", 0), Token(TokenType.EndOfFile, "", 1));
 			AssertTokensMatch("==", Token(TokenType.Equal, "==", 0), Token(TokenType.EndOfFile, "", 2));
 			AssertTokensMatch("!=", Token(TokenType.NotEqual, "!=", 0), Token(TokenType.EndOfFile, "", 2));
+			AssertTokensMatch("<>", Token(TokenType.NotEqual, "<>", 0), Token(TokenType.EndOfFile, "", 2));
 			AssertTokensMatch("(", Token(TokenType.LeftParenthesis, "(", 0), Token(TokenType.EndOfFile, "", 1));
 			AssertTokensMatch(")", Token(TokenType.RightParenthesis, ")", 0), Token(TokenType.EndOfFile, "", 1));
 			AssertTokensMatch("+", Token(TokenType.Plus, "+", 0), Token(TokenType.EndOfFile, "", 1));

shunting_yard/src/tokenizer/Tokenizer.cs

@@ -139,11 +139,12 @@ IEnumerable<Token> Scan()
 				if (IsWhiteSpace())
 				{
 					yield return ScanWhiteSpace();
-				} 
+				}
 				else if (IsDigit())
 				{
 					yield return ScanInteger();
-				} else if (Peek() == '.')
+				}
+				else if (Peek() == '.')
 				{
 					yield return ScanFloatingPointNumber();
 				}
@@ -271,6 +272,11 @@ Token ScanPunctuation()
 						Consume();
 						return CreateToken(TokenType.LessOrEqual);
 					}
+					if (Peek() == '>')
+					{
+						Consume();
+						return CreateToken(TokenType.NotEqual);
+					}
 					return CreateToken(TokenType.Less);
 				case '+':
 					Consume();