private static LambdaExpression CreateLambdaExpression(Expression body,
ParameterExpression[] parameterExpressions)
{
var types = new Type[parameterExpressions.Length + 1];
if (parameterExpressions.Length > 0)
{
var set = new HashSet <ParameterExpression>();
for (int index = 0; index < parameterExpressions.Length; ++index)
{
ParameterExpression parameterExpression = parameterExpressions[index];
types[index] = !parameterExpression.IsByRef
? parameterExpression.Type
: parameterExpression.Type.MakeByRefType();
if (set.Contains(parameterExpression))
{
throw BindingExtensions.DuplicateLambdaParameter(parameterExpression.ToString());
}
set.Add(parameterExpression);
}
}
types[parameterExpressions.Length] = body.Type;
Type delegateType = Expression.GetDelegateType(types);
return(CreateLambdaExpressionByType(delegateType, body, parameterExpressions));
}
