internal static DynamicMetaObject Bind(
DynamicMetaObjectBinder action,
RuntimeBinder binder,
IEnumerable <DynamicMetaObject> args,
IEnumerable <CSharpArgumentInfo> arginfos,
DynamicMetaObject onBindingError)
{
List <Expression> parameters = new List <Expression>();
BindingRestrictions restrictions = BindingRestrictions.Empty;
ICSharpInvokeOrInvokeMemberBinder callPayload = action as ICSharpInvokeOrInvokeMemberBinder;
ParameterExpression tempForIncrement = null;
IEnumerator <CSharpArgumentInfo> arginfosEnum = arginfos == null ? null : arginfos.GetEnumerator();
int index = 0;
foreach (DynamicMetaObject o in args)
{
// Our contract with the DLR is such that we will not enter a bind unless we have
// values for the meta-objects involved.
if (!o.HasValue)
{
Debug.Assert(false, "The runtime binder is being asked to bind a metaobject without a value");
throw Error.InternalCompilerError();
}
CSharpArgumentInfo info = null;
if (arginfosEnum != null && arginfosEnum.MoveNext())
{
info = arginfosEnum.Current;
}
if (index == 0 && IsIncrementOrDecrementActionOnLocal(action))
{
// We have an inc or a dec operation. Insert the temp local instead.
//
// We need to do this because for value types, the object will come
// in boxed, and we'd need to unbox it to get the original type in order
// to increment. The only way to do that is to create a new temporary.
tempForIncrement = Expression.Variable(o.Value != null ? o.Value.GetType() : typeof(object), "t0");
parameters.Add(tempForIncrement);
}
else
{
parameters.Add(o.Expression);
}
BindingRestrictions r = DeduceArgumentRestriction(index, callPayload, o, info);
restrictions = restrictions.Merge(r);
// Here we check the argument info. If the argument info shows that the current argument
// is a literal constant, then we also add an instance restriction on the value of
// the constant.
if (info != null && info.LiteralConstant)
{
if ((o.Value is float && float.IsNaN((float)o.Value)) ||
o.Value is double && double.IsNaN((double)o.Value))
{
// We cannot create an equality restriction for NaN, because equality is implemented
// in such a way that NaN != NaN and the rule we make would be unsatisfiable.
}
else
{
Expression e = Expression.Equal(o.Expression, Expression.Constant(o.Value, o.Expression.Type));
r = BindingRestrictions.GetExpressionRestriction(e);
restrictions = restrictions.Merge(r);
}
}
++index;
}
// Get the bound expression.
try
{
DynamicMetaObject deferredBinding;
Expression expression = binder.Bind(action, parameters, args.ToArray(), out deferredBinding);
if (deferredBinding != null)
{
expression = ConvertResult(deferredBinding.Expression, action);
restrictions = deferredBinding.Restrictions.Merge(restrictions);
return(new DynamicMetaObject(expression, restrictions));
}
if (tempForIncrement != null)
{
// If we have a ++ or -- payload, we need to do some temp rewriting.
// We rewrite to the following:
//
// temp = (type)o;
// temp++;
// o = temp;
// return o;
DynamicMetaObject arg0 = Enumerable.First(args);
Expression assignTemp = Expression.Assign(
tempForIncrement,
Expression.Convert(arg0.Expression, arg0.Value.GetType()));
Expression assignResult = Expression.Assign(
arg0.Expression,
Expression.Convert(tempForIncrement, arg0.Expression.Type));
List <Expression> expressions = new List <Expression>();
expressions.Add(assignTemp);
expressions.Add(expression);
expressions.Add(assignResult);
expression = Expression.Block(new ParameterExpression[] { tempForIncrement }, expressions);
}
expression = ConvertResult(expression, action);
return(new DynamicMetaObject(expression, restrictions));
}
catch (RuntimeBinderException e)
{
if (onBindingError != null)
{
return(onBindingError);
}
return(new DynamicMetaObject(
Expression.Throw(
Expression.New(
typeof(RuntimeBinderException).GetConstructor(new Type[] { typeof(string) }),
Expression.Constant(e.Message)
),
GetTypeForErrorMetaObject(action, args.FirstOrDefault())
),
restrictions
));
}
}
internal static DynamicMetaObject Bind(
ICSharpBinder action,
RuntimeBinder binder,
DynamicMetaObject[] args,
IEnumerable <CSharpArgumentInfo> arginfos,
DynamicMetaObject onBindingError)
{
Expression[] parameters = new Expression[args.Length];
BindingRestrictions restrictions = BindingRestrictions.Empty;
ICSharpInvokeOrInvokeMemberBinder callPayload = action as ICSharpInvokeOrInvokeMemberBinder;
ParameterExpression tempForIncrement = null;
IEnumerator <CSharpArgumentInfo> arginfosEnum = (arginfos ?? Array.Empty <CSharpArgumentInfo>()).GetEnumerator();
for (int index = 0; index < args.Length; ++index)
{
DynamicMetaObject o = args[index];
// Our contract with the DLR is such that we will not enter a bind unless we have
// values for the meta-objects involved.
Debug.Assert(o.HasValue);
CSharpArgumentInfo info = arginfosEnum.MoveNext() ? arginfosEnum.Current : null;
if (index == 0 && IsIncrementOrDecrementActionOnLocal(action))
{
// We have an inc or a dec operation. Insert the temp local instead.
//
// We need to do this because for value types, the object will come
// in boxed, and we'd need to unbox it to get the original type in order
// to increment. The only way to do that is to create a new temporary.
object value = o.Value;
tempForIncrement = Expression.Variable(value != null ? value.GetType() : typeof(object), "t0");
parameters[0] = tempForIncrement;
}
else
{
parameters[index] = o.Expression;
}
BindingRestrictions r = DeduceArgumentRestriction(index, callPayload, o, info);
restrictions = restrictions.Merge(r);
// Here we check the argument info. If the argument info shows that the current argument
// is a literal constant, then we also add an instance restriction on the value of
// the constant.
if (info != null && info.LiteralConstant)
{
if (o.Value is double && double.IsNaN((double)o.Value))
{
MethodInfo isNaN = s_DoubleIsNaN ?? (s_DoubleIsNaN = typeof(double).GetMethod("IsNaN"));
Expression e = Expression.Call(null, isNaN, o.Expression);
restrictions = restrictions.Merge(BindingRestrictions.GetExpressionRestriction(e));
}
else if (o.Value is float && float.IsNaN((float)o.Value))
{
MethodInfo isNaN = s_SingleIsNaN ?? (s_SingleIsNaN = typeof(float).GetMethod("IsNaN"));
Expression e = Expression.Call(null, isNaN, o.Expression);
restrictions = restrictions.Merge(BindingRestrictions.GetExpressionRestriction(e));
}
else
{
Expression e = Expression.Equal(o.Expression, Expression.Constant(o.Value, o.Expression.Type));
r = BindingRestrictions.GetExpressionRestriction(e);
restrictions = restrictions.Merge(r);
}
}
}
// Get the bound expression.
try
{
Expression expression = binder.Bind(action, parameters, args, out DynamicMetaObject deferredBinding);
if (deferredBinding != null)
{
expression = ConvertResult(deferredBinding.Expression, action);
restrictions = deferredBinding.Restrictions.Merge(restrictions);
return(new DynamicMetaObject(expression, restrictions));
}
if (tempForIncrement != null)
{
// If we have a ++ or -- payload, we need to do some temp rewriting.
// We rewrite to the following:
//
// temp = (type)o;
// temp++;
// o = temp;
// return o;
DynamicMetaObject arg0 = args[0];
expression = Expression.Block(
new[] { tempForIncrement },
Expression.Assign(tempForIncrement, Expression.Convert(arg0.Expression, arg0.Value.GetType())),
expression,
Expression.Assign(arg0.Expression, Expression.Convert(tempForIncrement, arg0.Expression.Type)));
}
expression = ConvertResult(expression, action);
return(new DynamicMetaObject(expression, restrictions));
}
catch (RuntimeBinderException e)
{
if (onBindingError != null)
{
return(onBindingError);
}
return(new DynamicMetaObject(
Expression.Throw(
Expression.New(
typeof(RuntimeBinderException).GetConstructor(new Type[] { typeof(string) }),
Expression.Constant(e.Message)
),
GetTypeForErrorMetaObject(action, args)
),
restrictions
));
}
}
