protected Type checkRelationalOp(Type t1, Type t2, Token op) {
// Checks Relational operators <, >, <=, >=, ==, and !=
if (t1.isArrayKind()) {
System.out.println(
"line " + op.getLine() + ": invalid argument 1 -- arrays cannot be compared");
errorCount++;
}
if (t2.isArrayKind()) {
System.out.println(
"line " + op.getLine() + ": invalid argument 2 -- arrays cannot be compared");
errorCount++;
}
if (!t1.isErrorType() && !t2.isErrorType()) {
if (!t1.isSameType(t2)) {
if (!t1.isNumericType() || !t2.isNumericType()) {
System.out.println(
"line "
+ op.getLine()
+ ": operands to relational operator `"
+ op.getText()
+ "' have incompatible types");
errorCount++;
}
}
}
return Type.boolValue;
} /* End of checkRelationalOp */
protected Type checkBinaryNumericOp(Node exp1, Node exp2, Token op) {
// Checks Binary operators +, -, *, /, and %
// Do not forget to handle + for pairs of strings.
Type t1 = null; // the type attribute of exp1
Type t2 = null; // the type attribute of exp2
// Below are the error messages to be printed when
// the type is wrong. The first is for t1 and second for t2.
System.out.println(
"line "
+ op.getLine()
+ ": invalid argument 1 ` "
+ exp1
+ "' for arithmetic operator `"
+ op.getText()
+ "'\n"
+ " -- expects a numeric argument but found "
+ t1.toString());
System.out.println(
"line "
+ op.getLine()
+ ": invalid argument 2 ` "
+ exp2
+ "' for arithmetic operator `"
+ op.getText()
+ "'\n"
+ " -- expects a numeric argument but found "
+ t2.toString());
return null;
} /* End of checkBinaryNumericOp */
protected Type checkUnaryNumericOp(Type t, Token op) {
// Checks Unary operators + and -
if (t.isArrayKind()) {
System.out.println(
"line "
+ op.getLine()
+ ": invalid argument to operator `"
+ op.getText()
+ "'\n"
+ " -- expects a numeric argument but found "
+ t.toString()
+ "[]");
errorCount++;
return Type.errorType;
}
if (t.isNumericType()) {
if (t.isCharType() && op.getText().equals("-")) {
return Type.intValue;
} else {
return t;
}
} else {
System.out.println(
"line "
+ op.getLine()
+ ": invalid argument type for unary operator `"
+ op.getText()
+ "'\n"
+ " -- expects a numeric argument but found "
+ t.toString());
errorCount++;
return Type.errorType;
}
} /* End of checkUnaryNumericOp */
protected Type checkUnaryBooleanOp(Type t, Token op) {
// Checks Unary operator !
if (t.isArrayKind()) {
System.out.println(
"line "
+ op.getLine()
+ ": invalid argument to operator `"
+ op.getText()
+ "'\n"
+ " -- expects a boolean argument but found "
+ t.toString()
+ "[]");
errorCount++;
return Type.boolValue;
}
if (t.isBoolType()) {
return t;
} else {
System.out.println(
"line "
+ op.getLine()
+ ": unary operator `!' expects a boolean argument "
+ "but found "
+ t.toString());
errorCount++;
return Type.boolValue;
}
} /* End of checkUnaryBooleanOp */
protected Type checkCondition(Type t1, Token op) {
// Checks conditional expressions in if and while statements
if (t1.isArrayKind()) {
System.out.println(
"line " + op.getLine() + ": a conditional expression must be a boolean type");
errorCount++;
return Type.boolValue;
}
if (!t1.isBoolType() && !t1.isErrorType()) {
System.out.println(
"line " + op.getLine() + ": a conditional expression must be a boolean type");
errorCount++;
}
return Type.boolValue;
} /* End of checkCondition */
protected Type checkLogicalOp(Type t1, Type t2, Token op) {
// Checks Logical operators || and &&
if (t1.isArrayKind()) {
System.out.println(
"line "
+ op.getLine()
+ ": invalid argument 1 to operator `"
+ op.getText()
+ "'\n"
+ " -- expects a boolean argument but found "
+ t1.toString()
+ "[]");
errorCount++;
return Type.boolValue;
}
if (t2.isArrayKind()) {
System.out.println(
"line "
+ op.getLine()
+ ": invalid argument 2 to operator `"
+ op.getText()
+ "'\n"
+ " -- expects a boolean argument but found "
+ t2.toString()
+ "[]");
errorCount++;
return Type.boolValue;
}
if (!t1.isBoolType() && !t1.isErrorType()) {
System.out.println(
"line "
+ op.getLine()
+ ": invalid argument 1 to operator `"
+ op.getText()
+ "'\n"
+ " -- expects a boolean argument but found "
+ t1.toString());
errorCount++;
}
if (!t2.isBoolType() && !t2.isErrorType()) {
System.out.println(
"line "
+ op.getLine()
+ ": invalid argument 2 to operator `"
+ op.getText()
+ "'\n"
+ " -- expects a boolean argument but found "
+ t2.toString());
errorCount++;
}
return Type.boolValue;
} /* End of checkLogicalOp */