/**
* Returns true if this is equal to that. This is true iff that is a structured type with the same
* fields as this.
*
* @param that type to compare to
* @return true if this and that are the same type
*/
public boolean equals(Object that) {
if (!(that instanceof TypeStruct)) return false;
TypeStruct ts = (TypeStruct) that;
// that must have exactly as many fields as this.
if (that.getNumFields() != this.getNumFields()) return false;
// loop through:
for (int i = 0; i < getNumFields(); i++) {
if (!(getName(i).equals(ts.getName(i)))) return false;
if (!(getType(i).equals(ts.getType(i)))) return false;
}
return true;
}
/**
* Return true if this can be converted to that without penalty. This is true if that is also a
* structured type, and that's fields are a superset of this's and in the same order.
*
* @param that type to compare to
* @return true if this can be converted to that without penalty
*/
public boolean isConvertibleTo(Type that) {
// Two cases that are interesting: either (1) that is also
// a TypeStruct that is a superset of this, or (2) that is a
// TypeLaidOut that is a valid layout of this.
if (that instanceof TypeStruct) {
TypeStruct ts = (TypeStruct) that;
// that must have at least as many fields as this.
if (that.getNumFields() < this.getNumFields()) return false;
// loop through:
for (int i = 0; i < getNumFields(); i++) {
if (!(getName(i).equals(ts.getName(i)))) return false;
if (!(getType(i).isConvertibleTo(ts.getType(i)))) return false;
}
return true;
} else return false;
}