dotnet/roslyn

IntelliSense complaining about not being able to find a type at assignment to "var"

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#11,084 opened on May 5, 2016

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 (2 comments) (0 reactions) (0 assignees)C# (20,414 stars) (4,257 forks)batch import
Area-CompilersBugConcept-Diagnostic Clarityhelp wanted

Description

Not sure if this by design, but it feels wrong - there's nothing I can do resolve this at the callsite:

image

The real problem is the declaration:

image

I can get together a repro (it's convoluted), but just wanted to confirm if this by design or not.

Contributor guide

Tech stack
csharp
Domain
developer experience
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
5
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
over 1 week
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
needs investigation
Prerequisites
C#Basic understanding of Roslyn's type system
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
10
Research direction
Investigate the type inference for var declarations in Roslyn's IntelliSense layer. Look at the binder or type checking code to understand the expected behavior. The issue mentions a convoluted repro, so try to create a minimal reproduction. Check if this is a known limitation or a bug in the semantic model.