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public static class GenericOperator<T>
{
    private static Func<T, T, TResult> CreateCore<TResult>(Func<Expression, Expression, BinaryExpression> body)
    {
        try
        {
            Type typeT = typeof(T);
            var left = Expression.Parameter(typeT, "left");
            var right = Expression.Parameter(typeT, "right");
 
            if (typeT.IsEnum)
            {
                Type enumType = Enum.GetUnderlyingType(typeT);
                var x = Expression.Convert(left, enumType);
                var y = Expression.Convert(right, enumType);
 
                Expression op = body(x, y);
                if (op.Type == enumType) op = Expression.Convert(op, typeT);
 
                return Expression.Lambda<Func<T, T, TResult>>(op, left, right).Compile();
            }
 
            return Expression.Lambda<Func<T, T, TResult>>(body(left, right), left, right).Compile();
        }
        catch (InvalidOperationException ex)
        {
            string message = ex.Message;
            return delegate { throw new InvalidOperationException(message); };
        }
        catch (ArgumentException ex)
        {
            string message = ex.Message;
            return delegate { throw new InvalidOperationException(message); };
        }
    }
 
    private static Lazy<Func<T, T, TResult>> Create<TResult>(Func<Expression, Expression, BinaryExpression> body)
    {
        return new Lazy<Func<T, T, TResult>>(() => CreateCore<TResult>(body), true);
    }
 
    private static readonly Lazy<Func<T, T, T>> _add = Create<T>(Expression.Add);
 
    public static Func<T, T, T> Add
    {
        get { return _add.Value; }
    }
 
    ...
}

Sanmayce wrote:

I see no problem(s) at all, that's why I am asking.

Sanmayce wrote:

Are you sure, I am not

Sanmayce wrote:

something as general and important as hashing for lookups deserves special page

Sanmayce wrote:

Thank you, obviously my articles are not even articles, sorry, but blame me not - that's me, a C amateur trying to test/share interesting etudes.

Quote:

Among the materials prominent in the Snowden files are the agency’s shared “wikis,” databases to which intelligence analysts, operatives and others contributed their knowledge

Mike Hankey wrote:

They want their privacy?...so do we!