/**
* Generates the relation field over the model sigs for called relations Must be run before the
* relation constraint is created (otherwise recursive calls will fail)
*
* @return the Alloy field for this relation
* @throws EchoError
* @todo Support for n models
*/
private Field addRelationFields() throws EchoError {
Field field = null;
Decl fst = rootvar2alloydecl.get(relation.getDomains().get(0).getRootVariable().getName());
/*Decl snd = rootvar2alloydecl.get(relation.getDomains().get(1)
.getVariable().getName());*/
try {
Sig s = (Sig) fst.expr.type().toExpr();
for (Field f : s.getFields()) {
if (f.label.equals(AlloyUtil.relationFieldName(relation, dependency.target))) field = f;
}
if (field == null) {
field =
s.addField(
AlloyUtil.relationFieldName(relation, dependency.target),
/*type.setOf()*/ Sig.UNIV.setOf());
}
} catch (Err a) {
throw new ErrorAlloy(
ErrorAlloy.FAIL_CREATE_FIELD,
"Failed to create relation field representation: " + relation.getName(),
a,
Task.TRANSLATE_TRANSFORMATION);
}
return field;
}
/**
* adds to the transformation translator the field representing this sub relation
*
* @throws EchoError
*/
private Field addRelationField() throws EchoError {
Field field = null;
try {
field = addRelationFields();
transformation_translator.addSubRelationCall(
new Func(
null,
AlloyUtil.relationFieldName(relation, dependency.target),
model_params_decls,
field.type().toExpr(),
field));
} catch (Err a) {
throw new ErrorAlloy(
ErrorAlloy.FAIL_CREATE_FUNC,
"Failed to create sub relation constraint function: " + relation.getName(),
a,
Task.TRANSLATE_TRANSFORMATION);
}
return field;
}
