internal FieldInfo GetDynamicConvertBinder(Type type, Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags flags)
{
FieldInfo field;
Tuple <Type, Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags> key = new Tuple <Type, Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags>(type, flags);
this.ConvertBinders.TryGetValue(key, out field);
if (field != null)
{
return(field);
}
string nameSuggestion = String.Format("{0}_{1}", flags, type.Name).Replace(" ", "").Replace("|", "_").Replace(",", "_");
string name = nameSuggestion;
for (int i = 1; ; i++)
{
if (!this.ConvertBinders.Values.Any(f => f.Name == name))
{
break;
}
name = String.Format("{0}_{1}", nameSuggestion, i);
}
field = this.ConvertBinderType.DefineField(name,
typeof(ConvertBinder),
FieldAttributes.Static | FieldAttributes.InitOnly | FieldAttributes.Assembly);
this.ConvertBinders.Add(key, field);
return(field);
}
public Expression CompileDynamicConvert(CompilationContext context, Expression parameter, Type type, ExpressionCompiler.Primitives.Conversion conversion)
{
// This is the tricky part ....
//
// Example that will NOT WORK:
// Int16 i16 = 123;
// Object o16 = i16;
// Int32 i32 = (Int32) o16 // *** FAILS *** ... even if object currently has an Int16, it's an object and no cast to Int32!
//
// Example that works:
// Int16 i16 = 123;
// Object o16 = i16;
// Int32 i32 = (Int16) o16 // OK! First cast Object=>Int16 then IMPLICIT cast Int16=>Int32
//
// VERY IMPORTANT!!!!
// This should ONLY do implicit conversion AND NO EXPLICIT conversions.
// If we do explicit conversion, we are screwed because the value
// will loose precision - and this is critical show stopper!
//
// C# Pseudocode Example ... cast to Int32:
// if (obj is Int32)
// return (Int32) obj;
// else
// return (Int32) ((dynamic) obj); // This uses a CallSite and a C# CallSiteBinder to do the cast.
//
// The DLR does not provide an easy helper function. So we have two options:
// 1. Write the logic for what converts implicitly to what (incl. dynamic cast). Too much work currently.
// 2. Use the C# binder to do the work. We actually WANT the same semantics as C#, so that's OK. But we depend on them :-/
Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags flags = Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags.None;
if ((conversion & Conversion.Checked) == Conversion.Checked)
{
flags = flags | Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags.CheckedContext;
}
if ((conversion & Conversion.Explicit) == Conversion.Explicit)
{
flags = flags | Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags.ConvertExplicit;
}
// Create a C# convert binder. Currently, this is not cached, but we could do this in the future.
ConvertBinderDefinition binder = new ConvertBinderDefinition(this.Client.Compiler.GetDynamicConvertBinder(type, flags));
// Create a call site
Type delegateType = typeof(Func <, ,>).MakeGenericType(typeof(CallSite), parameter.Type, type);
Type siteType = typeof(CallSite <>).MakeGenericType(delegateType);
Expression callSite = this.CallSiteGenerator.CreateCallSite(binder, delegateType, siteType, String.Format("({0})", type.Name));
FieldInfo target = TypeUtilities.Field(siteType, "Target", BindingFlags.Instance | BindingFlags.Public);
MethodInfo invoke = TypeUtilities.Method(delegateType, "Invoke");
// siteExpr.Target.Invoke(siteExpr, parameter)
return(Expression.Call(
Expression.Field(callSite, target),
invoke,
callSite, parameter));
}
public Expression CompileDynamicConvert(CompilationContext context, Expression parameter, Type type, Primitives.Conversion conversion)
{
// This is the tricky part ....
//
// Example that will NOT WORK:
// Int16 i16 = 123;
// Object o16 = i16;
// Int32 i32 = (Int32) o16 // *** FAILS *** ... even if object currently has an Int16, it's an object and no cast to Int32!
//
// Example that works:
// Int16 i16 = 123;
// Object o16 = i16;
// Int32 i32 = (Int16) o16 // OK! First cast Object=>Int16 then IMPLICIT cast Int16=>Int32
//
// VERY IMPORTANT!!!!
// This should ONLY do implicit conversion AND NO EXPLICIT conversions.
// If we do explicit conversion, we are screwed because the value
// will loose precision - and this is critical show stopper!
//
// C# Pseudocode Example ... cast to Int32:
// if (obj is Int32)
// return (Int32) obj;
// else
// return (Int32) ((dynamic) obj); // This uses a CallSite and a C# CallSiteBinder to do the cast.
//
// The DLR does not provide an easy helper function. So we have two options:
// 1. Write the logic for what converts implicitly to what (incl. dynamic cast). Too much work currently.
// 2. Use the C# binder to do the work. We actually WANT the same semantics as C#, so that's OK. But we depend on them :-/
Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags flags = Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags.None;
if ((conversion & Conversion.Checked) == Conversion.Checked)
{
flags = flags | Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags.CheckedContext;
}
if ((conversion & Conversion.Explicit) == Conversion.Explicit)
{
flags = flags | Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags.ConvertExplicit;
}
// Create a C# convert binder. Currently, this is not cached, but we could do this in the future.
Tuple <Type, Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags> key = new Tuple <Type, Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags>(type, flags);
ConvertBinder binder = DynamicCallStrategy.ConvertBinders.GetOrAdd(key, k => (ConvertBinder)Microsoft.CSharp.RuntimeBinder.Binder.Convert(k.Item2, k.Item1, typeof(DynamicCallStrategy)));
// Create a call site
Type delegateType = typeof(Func <, ,>).MakeGenericType(typeof(CallSite), parameter.Type, type);
return(Expression.MakeDynamic(delegateType, binder, parameter));
}
public static System.Runtime.CompilerServices.CallSiteBinder UnaryOperation(Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags flags, System.Linq.Expressions.ExpressionType operation, System.Type context, System.Collections.Generic.IEnumerable <Microsoft.CSharp.RuntimeBinder.CSharpArgumentInfo> argumentInfo)
{
throw null;
}
public static System.Runtime.CompilerServices.CallSiteBinder SetMember(Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags flags, string name, System.Type context, System.Collections.Generic.IEnumerable <Microsoft.CSharp.RuntimeBinder.CSharpArgumentInfo> argumentInfo)
{
throw null;
}
public static System.Runtime.CompilerServices.CallSiteBinder IsEvent(Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags flags, string name, System.Type context)
{
throw null;
}
public static System.Runtime.CompilerServices.CallSiteBinder Convert(Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags flags, System.Type type, System.Type context)
{
throw null;
}
public static System.Runtime.CompilerServices.CallSiteBinder InvokeConstructor(Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags flags, System.Type?context, System.Collections.Generic.IEnumerable <Microsoft.CSharp.RuntimeBinder.CSharpArgumentInfo>?argumentInfo)
{
throw null;
}
public static System.Runtime.CompilerServices.CallSiteBinder SetIndex(Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags flags, System.Type context, System.Collections.Generic.IEnumerable <Microsoft.CSharp.RuntimeBinder.CSharpArgumentInfo> argumentInfo)
{
return(default(System.Runtime.CompilerServices.CallSiteBinder));
}
public static System.Runtime.CompilerServices.CallSiteBinder IsEvent(Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags flags, string name, System.Type context)
{
return(default(System.Runtime.CompilerServices.CallSiteBinder));
}
public static System.Runtime.CompilerServices.CallSiteBinder Convert(Microsoft.CSharp.RuntimeBinder.CSharpBinderFlags flags, System.Type type, System.Type context)
{
return(default(System.Runtime.CompilerServices.CallSiteBinder));
}
