Visual Studio 2015 false alarm out keyword reference types as method arguments

Question

I'm using unity with C# in Visual Studio 2015 and whenever I use something like this:

if (!NavMesh.SamplePosition(position, out NavMeshHit hit, 1f, NavMesh.AllAreas)) { return; }

or this

if (!Physics.Raycast(ray, out RaycastHit hit, Mathf.Infinity)) { return; }

I get a compile time error warning for RaycastHit hit or NavMeshHit hit and where ever hit is used after that. if I declare it as local variable the error goes away

NavMeshHit hit;
if (!NavMesh.SamplePosition(position, out hit, 1f, NavMesh.AllAreas)) { return; }

RaycastHit hit;
if (!Physics.Raycast(ray, out hit, Mathf.Infinity)) { return; }

or by pressing Ctrl + . and then Esc canceling it, the error goes away and even if it doesn't, it just compiles OK and goes into run-time with no problem.

is there a way to resolve this inside visual studio?

What is the actual error message, or is it a warning, what is it? — Charlieface, Mar 07 '21 at 13:54
This is a C# 7 feature so you need at least Visual Studio 2017 — Klaus Gütter, Mar 07 '21 at 15:23
@KlausGütter what is the name of this feature, I don't even know what to search to look for any plugin or workaround, is there a way to turn of that specific warning? — Alireza Jamali, Mar 07 '21 at 19:38
@Charlieface 'NavMeshHit' is a type but is used like a variable, KlausGütter is right, it seems I need to whether switch to 2017 or just ignore it. — Alireza Jamali, Mar 07 '21 at 19:42
https://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-7#out-variables — Klaus Gütter, Mar 07 '21 at 21:03
btw this one helped https://stackoverflow.com/questions/39461407/how-to-use-c-sharp-7-with-visual-studio-2015 — Alireza Jamali, Mar 08 '21 at 06:13

Alireza Jamali · Accepted Answer · 2021-03-11T06:08:25.477

0

It's a C# 7 feature not available in Visual Studio 2015, you have to whether upgrade to 2017 or just ignore it.

EDIT: ended up using Visual Studio Code at the end, coz for me Visual Studio 2017 was too much of a size, 50GB compared to 2015 with only 9GB

edited Mar 11 '21 at 06:08

answered Mar 09 '21 at 07:23

Alireza Jamali

302
2
6
17

Visual Studio 2015 false alarm out keyword reference types as method arguments

1 Answers1