private static Expression Variable(IScopeVariable variable)
{
return(Expression.Convert(
Expression.Property(
Expression.Constant(((IWeakReferencable)variable).WeakReference),
typeof(WeakReference).GetProperty("Target")
),
variable.GetType()
));
}
public override DynamicMetaObject BindDeleteMember(DeleteMemberBinder binder)
{
IScopeVariable variable = Value.GetScopeVariable(binder.Name, binder.IgnoreCase);
return(new DynamicMetaObject(
Expression.Condition(
Expression.Call(
Variable(variable),
variable.GetType().GetMethod("DeleteValue")
),
Expression.Default(binder.ReturnType),
binder.FallbackDeleteMember(this).Expression
),
BindingRestrictions.GetInstanceRestriction(Expression, Value)
));
}
public override DynamicMetaObject BindSetMember(SetMemberBinder binder, DynamicMetaObject value)
{
IScopeVariable variable = Value.GetScopeVariable(binder.Name, binder.IgnoreCase);
var objExpression = ExpressionUtils.Convert(value.Expression, typeof(object));
return(new DynamicMetaObject(
Expression.Block(
Expression.Call(
Variable(variable),
variable.GetType().GetMethod("SetValue"),
objExpression
),
objExpression
),
BindingRestrictions.GetInstanceRestriction(Expression, Value)
));
}
private DynamicMetaObject DynamicTryGetValue(string name, bool ignoreCase, Expression fallback, Func <Expression, Expression> resultOp)
{
IScopeVariable variable = Value.GetScopeVariable(name, ignoreCase);
var tmp = Expression.Parameter(typeof(object));
return(new DynamicMetaObject(
Expression.Block(
new[] { tmp },
Expression.Condition(
Expression.Call(
Variable(variable),
variable.GetType().GetMethod("TryGetValue"),
tmp
),
ExpressionUtils.Convert(resultOp(tmp), typeof(object)),
ExpressionUtils.Convert(fallback, typeof(object))
)
),
BindingRestrictions.GetInstanceRestriction(Expression, Value)
));
}
private static Expression Variable(IScopeVariable variable) {
return Expression.Convert(
Expression.Property(
Expression.Constant(((IWeakReferencable)variable).WeakReference),
typeof(WeakReference).GetProperty("Target")
),
variable.GetType()
);
}
