public override bool Equals(object obj) {
ComboBinder other = obj as ComboBinder;
if (other != null) {
if (_metaBinders.Length != other._metaBinders.Length) {
return false;
}
for (int i = 0; i < _metaBinders.Length; i++) {
BinderMappingInfo self = _metaBinders[i];
BinderMappingInfo otherBinders = other._metaBinders[i];
if (!self.Binder.Equals(otherBinders.Binder) ||
self.MappingInfo.Count != otherBinders.MappingInfo.Count) {
return false;
}
for (int j = 0; j < self.MappingInfo.Count; j++) {
if (!self.MappingInfo[j].Equals(otherBinders.MappingInfo[j])) {
return false;
}
}
}
return true;
}
return false;
}
private DynamicMetaObject[] GetArguments(DynamicMetaObject[] args, IList<DynamicMetaObject> results, int metaBinderIndex) {
BinderMappingInfo indices = _metaBinders[metaBinderIndex];
DynamicMetaObject[] res = new DynamicMetaObject[indices.MappingInfo.Count];
for (int i = 0; i < res.Length; i++) {
ParameterMappingInfo mappingInfo = indices.MappingInfo[i];
if (mappingInfo.IsAction) {
// input is the result of a previous bind
res[i] = results[mappingInfo.ActionIndex];
} else if (mappingInfo.IsParameter) {
// input is one of the original arguments
res[i] = args[mappingInfo.ParameterIndex];
} else {
// input is a constant
res[i] = new DynamicMetaObject(
mappingInfo.Constant,
BindingRestrictions.Empty,
mappingInfo.Constant.Value
);
}
}
return res;
}
public override DynamicMetaObject Bind(DynamicMetaObject target, params DynamicMetaObject[] args)
{
args = ArrayUtils.Insert(target, args);
List <DynamicMetaObject> results = new List <DynamicMetaObject>(_metaBinders.Length);
List <Expression> steps = new List <Expression>();
List <ParameterExpression> temps = new List <ParameterExpression>();
BindingRestrictions restrictions = BindingRestrictions.Empty;
for (int i = 0; i < _metaBinders.Length; i++)
{
BinderMappingInfo curBinder = _metaBinders[i];
DynamicMetaObject[] tmpargs = GetArguments(args, results, i);
DynamicMetaObject next = curBinder.Binder.Bind(tmpargs[0], ArrayUtils.RemoveFirst(tmpargs));
if (i != 0)
{
// If the rule contains an embedded "update", replace it with a defer
var visitor = new ReplaceUpdateVisitor {
Binder = curBinder.Binder, Arguments = tmpargs
};
next = new DynamicMetaObject(visitor.Visit(next.Expression), next.Restrictions);
}
restrictions = restrictions.Merge(next.Restrictions);
if (next.Expression.NodeType == ExpressionType.Throw)
{
// end of the line... the expression is throwing, none of the other
// binders will have an opportunity to run.
steps.Add(next.Expression);
break;
}
ParameterExpression tmp = Expression.Variable(next.Expression.Type, "comboTemp" + i.ToString());
temps.Add(tmp);
steps.Add(Expression.Assign(tmp, next.Expression));
results.Add(new DynamicMetaObject(tmp, next.Restrictions));
}
return(new DynamicMetaObject(
Expression.Block(
temps.ToArray(),
steps.ToArray()
),
restrictions
));
}
public override MetaObject Bind(MetaObject target, params MetaObject[] args)
{
args = ArrayUtils.Insert(target, args);
List <MetaObject> results = new List <MetaObject>(_metaBinders.Length);
List <Expression> steps = new List <Expression>();
List <ParameterExpression> temps = new List <ParameterExpression>();
Restrictions restrictions = Restrictions.Empty;
for (int i = 0; i < _metaBinders.Length; i++)
{
BinderMappingInfo curBinder = _metaBinders[i];
MetaObject[] tmpargs = GetArguments(args, results, i);
MetaObject next = curBinder.Binder.Bind(tmpargs[0], ArrayUtils.RemoveFirst(tmpargs));
if (next.Expression.NodeType == ExpressionType.Throw)
{
// end of the line... the expression is throwing, none of the other
// binders will have an opportunity to run.
steps.Add(next.Expression);
break;
}
ParameterExpression tmp = Expression.Variable(next.Expression.Type, "comboTemp" + i.ToString());
temps.Add(tmp);
steps.Add(Expression.Assign(tmp, next.Expression));
results.Add(new MetaObject(tmp, next.Restrictions));
restrictions = restrictions.Merge(next.Restrictions);
}
return(new MetaObject(
Expression.Block(
temps.ToArray(),
steps.ToArray()
),
restrictions
));
}