public IObjField this[string field_name]
{
// TODO: 2010/04/08
// Determined that get and set BOTH need to ALWAYS auto-vivify the field.
// This is because someobj["some_field"].iv = 42 calls OBJ indexer property GET, and then FIELD property SET on the field that returns.
//
// In future, maybe some means of avoiding "needless" auto-vivification on get can be found,
// but it may be a non-critical optimization anyways -- that needs study to justify optimization effort
get
{
if (field_name == null)
{
Error.BadArg("Got null field_name");
}
if (!Token.is_bare_multi_word(field_name))
{
Error.BadArg("Got invalid field_name '{0}'", field_name);
}
if (!fields.ContainsKey(field_name))
{
// If the field is not present, auto-vivify the field from the Archetype's corresponding field
IArchetypeField arch_field = archetype[field_name];
if (arch_field == null)
{
// TODO: Policy control over behavior upon .get of a field not present in the Archetype.
// Default will likely be to auto-vivify and return default value?
//Form1.stdout.print("ObjField.get: found null archetype field for field_name '{0}', auto-vivifying.\n", field_name);
fields[field_name] = new FieldTempNull(this, field_name);
// Let's see if the FieldTempNull approach works...wow, surprisingly well at near-first test!
// Hmmm...if we don't have an Archetype field to get an IObjField from, how do we know what type to instantiate?
// Seems it will have to be fatal? I'd rather be able to auto-vivify, but this gets called _before_ the .set ...argh...
//Error.Throw("Somehow got null archetype arch_field for field_name '{0}'", field_name);
}
else
{
fields[field_name] = arch_field.default_value; // TODO: Verify that this is a "deep" copy, or deep enough at any rate...
}
}
return(fields[field_name]);
}
set
{
if (field_name == null)
{
Error.BadArg("Got null field_name");
}
if (!Token.is_bare_multi_word(field_name))
{
Error.BadArg("Got invalid field_name '{0}'", field_name);
}
if (archetype[field_name] != null)
{
SemanticTypes type_of_new_field = value.type.semantic_type;
SemanticTypes type_of_arch_field = archetype[field_name].type.semantic_type;
if (type_of_new_field != type_of_arch_field)
{
Error.BadArg("ObjField.set: Called for Obj '{0}' with Archetype '{1}' on field_name '{2}', " +
"with strange IObjField having semantic type '{3}' " +
"which differs from the archetype field semantic type '{4}'",
autotag, archetype.tag, field_name, type_of_new_field, type_of_arch_field);
}
}
//else
//{
// Form1.stdout.print("Obj.this[].set called for field '{0}', archetype does not contain that field\n", field_name);
//}
if (fields.ContainsKey(field_name) && fields[field_name].type != FieldType.EMPTY)
{
// Call to set for an already-present field.
// This is OK if the already-present field is a FieldTempNull... ???
// TODO: Should be controlled by a policy variable.
// A likely default would be to warn and replace the existing attribute.
Error.BadArg("Got already-present Obj parse_field_name '{0}'", field_name);
}
fields[field_name] = value;
}
} // this[field_name]
public IObjField this[string field_name]
{
// TODO: 2010/04/08
// Determined that get and set BOTH need to ALWAYS auto-vivify the field.
// This is because someobj["some_field"].iv = 42 calls OBJ indexer property GET, and then FIELD property SET on the field that returns.
//
// In future, maybe some means of avoiding "needless" auto-vivification on get can be found,
// but it may be a non-critical optimization anyways -- that needs study to justify optimization effort
get
{
if (field_name == null) { Error.BadArg("Got null field_name"); }
if (!Token.is_bare_multi_word(field_name)) { Error.BadArg("Got invalid field_name '{0}'", field_name); }
if (!fields.ContainsKey(field_name))
{
// If the field is not present, auto-vivify the field from the Archetype's corresponding field
IArchetypeField arch_field = archetype[field_name];
if (arch_field == null)
{
// TODO: Policy control over behavior upon .get of a field not present in the Archetype.
// Default will likely be to auto-vivify and return default value?
//Form1.stdout.print("ObjField.get: found null archetype field for field_name '{0}', auto-vivifying.\n", field_name);
fields[field_name] = new FieldTempNull(this, field_name);
// Let's see if the FieldTempNull approach works...wow, surprisingly well at near-first test!
// Hmmm...if we don't have an Archetype field to get an IObjField from, how do we know what type to instantiate?
// Seems it will have to be fatal? I'd rather be able to auto-vivify, but this gets called _before_ the .set ...argh...
//Error.Throw("Somehow got null archetype arch_field for field_name '{0}'", field_name);
}
else
{
fields[field_name] = arch_field.default_value; // TODO: Verify that this is a "deep" copy, or deep enough at any rate...
}
}
return fields[field_name];
}
set
{
if (field_name == null) { Error.BadArg("Got null field_name"); }
if (!Token.is_bare_multi_word(field_name)) { Error.BadArg("Got invalid field_name '{0}'", field_name); }
if (archetype[field_name] != null)
{
SemanticTypes type_of_new_field = value.type.semantic_type;
SemanticTypes type_of_arch_field = archetype[field_name].type.semantic_type;
if (type_of_new_field != type_of_arch_field)
{
Error.BadArg("ObjField.set: Called for Obj '{0}' with Archetype '{1}' on field_name '{2}', " +
"with strange IObjField having semantic type '{3}' " +
"which differs from the archetype field semantic type '{4}'",
autotag, archetype.tag, field_name, type_of_new_field, type_of_arch_field);
}
}
//else
//{
// Form1.stdout.print("Obj.this[].set called for field '{0}', archetype does not contain that field\n", field_name);
//}
if (fields.ContainsKey(field_name) && fields[field_name].type != FieldType.EMPTY)
{
// Call to set for an already-present field.
// This is OK if the already-present field is a FieldTempNull... ???
// TODO: Should be controlled by a policy variable.
// A likely default would be to warn and replace the existing attribute.
Error.BadArg("Got already-present Obj parse_field_name '{0}'", field_name);
}
fields[field_name] = value;
}
}