Mouse-over tooltips show "unknown identifier" over known variables at local methods in C#.


I'm new to Rider IDE so perhaps I'm just missing something.
When I'm debugging my code, which sometimes include local methods (i.e. methods within methods) and using a break-point within a local method, then any attempt to evaluate any variable which originates from the outer scope (i.e. the outer method body) will rather show "unknown identifier" in the tooltip, however these variables are actually well visible within the local method since local conditional expressions which rely on them seem to work & evaluate properly at run time (flow control works as expected) so why is the debugger failing to identify these variables?


I'm also having this issue (Rider 2018.1.2). Everything else works as expected. But sometimes I need to examine further properties of an object. It's pretty annoying just to read "Unknown Identifier"

Is this a bug or just missing a setting? 


.Net 4.6.1 wpf application


This is ridiculous. It makes you have to build to see the actual error. Please escalate.


Hrm. This may be a result of debugging. Don't have time to reproduce right now, but check if it only happens when debugging. (Oops)


Hello everyone,

Sorry for the delayed reply. We've just added a new expression evaluation engine to Rider, which must have fixed such issues. We'd be grateful if you could try the latest EAP build and let us know if everything is ok in your case.

Thank you!


I have this problem a lot, I tried the EAP build as recommended and it's exactly the same, sadly. Mouseover and adding watches works for only a handful of variables (those passed into a function seem OK, but ones that have just been created and assigned are all shown as 'Unknown identifier'). It's very troublesome, would love some solutions! Thanks!



Could you please comment on this issue on YouTrack and provide the following information:

1. What kind of project do you have? Is it .NET Framework/.NET Core/Mono?

2. What is the version of .NET Core/Mono (in case you use it)?

3. Please reproduce the issue on the latest EAP build (EAP 9) and collect Rider logs with "Help -> Compress log..."

Thank you! We'll do our best to fix the bug. 


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