--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/expression.h Sun Mar 30 21:51:23 2014 +0300
@@ -0,0 +1,132 @@
+#ifndef BOTC_EXPRESSION_H
+#define BOTC_EXPRESSION_H
+#include "parser.h"
+
+class DataBuffer;
+class ExpressionSymbol;
+class ExpressionValue;
+class ExpressionOperator;
+
+// =============================================================================
+//
+named_enum ExpressionOperatorType
+{
+ OPER_NegateLogical,
+ OPER_UnaryMinus,
+ OPER_Multiplication,
+ OPER_Division,
+ OPER_Modulus,
+ OPER_Addition,
+ OPER_Subtraction,
+ OPER_LeftShift,
+ OPER_RightShift,
+ OPER_CompareLesser,
+ OPER_CompareGreater,
+ OPER_CompareAtLeast,
+ OPER_CompareAtMost,
+ OPER_CompareEquals,
+ OPER_CompareNotEquals,
+ OPER_BitwiseAnd,
+ OPER_BitwiseXOr,
+ OPER_BitwiseOr,
+ OPER_LogicalAnd,
+ OPER_LogicalOr,
+ OPER_Ternary,
+};
+
+// =============================================================================
+//
+enum ExpressionSymbolType
+{
+ EXPRSYM_Operator,
+ EXPRSYM_Value,
+ EXPRSYM_Colon,
+};
+
+class Expression final
+{
+ public:
+ using SymbolList = List<ExpressionSymbol*>;
+
+ Expression (BotscriptParser* parser, Lexer* lx, DataType reqtype);
+ ~Expression();
+ ExpressionValue* getResult();
+
+ private:
+ BotscriptParser* m_parser;
+ Lexer* m_lexer;
+ SymbolList m_symbols;
+ DataType m_type;
+ String m_badTokenText;
+
+ ExpressionValue* evaluate(); // Process the expression and yield a result
+ ExpressionSymbol* parseSymbol();
+ String getTokenString();
+ void adjustOperators();
+ void verify(); // Ensure the expr is valid
+ void tryVerifyValue (bool* verified, SymbolList::Iterator it);
+ ExpressionValue* evaluateOperator (const ExpressionOperator* op,
+ const List<ExpressionValue*>& values);
+ SymbolList::Iterator findPrioritizedOperator();
+};
+
+// =============================================================================
+//
+class ExpressionSymbol
+{
+ public:
+ ExpressionSymbol (ExpressionSymbolType type) :
+ m_type (type) {}
+
+ PROPERTY (private, ExpressionSymbolType, type, setType, STOCK_WRITE)
+};
+
+// =============================================================================
+//
+class ExpressionOperator final : public ExpressionSymbol
+{
+ PROPERTY (public, ExpressionOperatorType, id, setID, STOCK_WRITE)
+
+ public:
+ ExpressionOperator (ExpressionOperatorType id);
+};
+
+// =============================================================================
+//
+class ExpressionValue final : public ExpressionSymbol
+{
+ PROPERTY (public, int, value, setValue, STOCK_WRITE)
+ PROPERTY (public, DataBuffer*, buffer, setBuffer, STOCK_WRITE)
+ PROPERTY (public, DataType, valueType, setValueType, STOCK_WRITE)
+
+ public:
+ ExpressionValue (DataType valuetype);
+ ~ExpressionValue();
+
+ void convertToBuffer();
+
+ inline ExpressionValue* clone() const
+ {
+ return new ExpressionValue (*this);
+ }
+
+ inline bool isConstexpr() const
+ {
+ return buffer() == null;
+ }
+};
+
+// =============================================================================
+//
+// This class represents a ":" in the expression. It serves as the colon for the
+// ternary ?: OPER_erator. It's not an OPER_erand nor is an OPER_erator, nor can we just
+// skip it so it is its own thing here.
+//
+class ExpressionColon final : public ExpressionSymbol
+{
+ public:
+ ExpressionColon() :
+ ExpressionSymbol (EXPRSYM_Colon) {}
+};
+
+#endif // BOTC_EXPRESSION_H