Getting magic strings from QueryOver (or maybe Fluent NHibernate)?

Question

One of the many reasons for using FluentNHibernate, the new QueryOver API, and the new Linq provider is all because they eliminate the “magic line” or lines representing properties or other things that might be presented at compile time.

Unfortunately, I am using spatial extensions for NHibernate that have not yet been updated to support QueryOver or LINQ. As a result, I am forced to use a combination of QueryOver Lambda expressions and strings to represent properties, etc., that I want to request.

I would like to do this - I want to ask Fluent NHibernate (or possibly the NHibernate QueryOver API) what the magic string should be. Here is an example of pseudo code:

I am currently writing -

var x = session.QueryOver<Shuttle>().Add(SpatialRestrictions.Intersects("abc", other_object));

What I would like to write is

var x = session.QueryOver<Shuttle>().Add(SpatialRestriction.Intersects(session.GetMagicString<Shuttle>(x => x.Abc), other_object));

Is there anything similar? Would it be hard to write?

EDIT: I just wanted to notice that this will be applied much more than just spatial. In fact, anything that has not been converted to QueryOver or LINQ can be useful.

Answer 1

Update

The nameof operator in C # 6 provides compile-time support for this.

---

There is a much simpler solution - expressions.

Take the following example:

public static class ExpressionsExtractor
{
    public static string GetMemberName<TObj, TProp>(Expression<Func<TObj, TProp>> expression)
    {
        var memberExpression = expression.Body as MemberExpression;

        if (memberExpression == null)
            return null;

        return memberExpression.Member.Name;
    }
}

And use:

var propName = ExpressionsExtractor.GetMemberName<Person, int>(p => p.Id);

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:

var abcPropertyName = ExpressionsExtractor.GetMemberName<Shuttle, IGeometry>(x => x.Abc);
var x = session.QueryOver<Shuttle>().Add(SpatialRestriction.Intersects(abcPropertyName, other_object));

Answer 2

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var x = session.QueryOver<Shuttle>().Add(SpatialRestrictions.Intersects(ShuttleHelper.Abc, other_object));

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var x = session.QueryOver<Shuttle>().Add(SpatialRestrictions.Intersects(ShuttleHelper.OtherObjectIntersectingColumn, other_object));

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