1. Declaration and Unicity. Review for uniqueness and that the variable has been declared before its usage. 2. Types. Review that the types of variables match the values assigned to them. 3. Array’s indexes. Review that the indexes are integers. 4. Conditions. Review that all expressions on the conditons return a boolean value. 5. Return type. Review that the value returned by a method match the type of the method. 6. Parameters. Review that the parameters in a method match in type and number with the declaration of the method.
be reported § Line <line>: Variable <variable> not found § Line <line>: Variable <variable> is already defined § Line <line>: Incompatible types: type mismatch § Line <line>: Incompatible types: expected boolean
1 1.Line 2: variable <boo> is already defined 2.Line 4: variable <k> is already defined 3.Line 8: incompatible types: type mismatch 4.Line 10: variable <hello> not found 5.Line 10: incompatible types: type mismatch 6.Line 18: boolean expression expected 7.Line 30: incompatible types: type mismatch 8.Line 34: incompatible types: type mismatch
þDeclaration and Unicity. Review for uniqueness and that the variable has been declared before its usage. þType Matching. Review that the types of variables match the values assigned to them. ¨Array’s indexes. Review that the indexes are integers. þConditions. Review that all expressions on the conditions return a boolean value. ¨Return type. Review that the value returned by a method matches the type of the method. ¨Parameters. Review that the parameters in a method match in type and number with the declaration of the method.
public class SemanticAnalyzer { private static final Hashtable<String, Vector<SymbolTableItem>> symbolTable; private static final Stack stack; // create here a data structure for the cube of types public static Hashtable<String, Vector<SymbolTableItem>> getSymbolTable() public static void checkVariable(String type, String id) public static String isBoolean() public static String isTypeMatching() public static void stackPush (String type) public static String stackPop() private String calculateType(String type, String operator) private String calculateType(String type1, String type2, String operator) private static void error(Gui gui, int error, int line, String info) }
Work 1. Functions: Grammar and Semantic Validation 2. Arrays: Grammar and Semantic Validation 3. Switch, For, and Do/While: Grammar and Semantic Validation 4. CallToMethod: Grammar and Semantic Validation
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