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Problem with nulls

Jun 23, 2015 at 7:55 AM
Edited Jun 23, 2015 at 11:50 AM
First of all thank you for your work.
I have to evaluate expressions like this
if(null!=10d) -> 'System.NullReferenceException'
if expression is like this if(10d!=null) it works fine, but I have to use both.
Any solution? thank you

At the moment I replace null by Double.NaN and condition like Double.IsNaN() but I dont like this solution...
Jun 24, 2015 at 7:14 AM
Edited Jun 24, 2015 at 7:20 AM
I appears that the expression is being converted into


hence the nullreferenceexception

This probably has to do with my type inference code that attempts to cast the left and right sides of a binary operation to the same type. There is probably something I misunderstood about type inference from the C# specification, and it's quite hard to implement correctly.

I will take a look at my code again and let you know once I fix it.

For now perhaps you can try casting 10d to object, if you want to test against null?
Jun 24, 2015 at 1:25 PM
Thank you very much. The problem is that expressions are stored in a database and writed by inexperienced users, so they must be friendly, like if(${Measured}>10d)......
Then I replace ${Measured} by some variable value, and this value can be null...
Thank you again for your library.