Bug 26569 - "using System.Math;" C# 6 syntax no longer works
Summary: "using System.Math;" C# 6 syntax no longer works
Alias: None
Product: Compilers
Classification: Mono
Component: C# ()
Version: unspecified
Hardware: PC Mac OS
: --- normal
Target Milestone: ---
Assignee: Marek Safar
Depends on:
Reported: 2015-01-29 15:01 UTC by Sandy Armstrong [MSFT]
Modified: 2015-02-10 04:13 UTC (History)
1 user (show)

Is this bug a regression?: ---
Last known good build:

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Description Sandy Armstrong [MSFT] 2015-01-29 15:01:27 UTC

1) Include a C# 6 style using statement like `using System.Math;` in your source
2) Compile

Expected results:

Compilation succeeds. You can then use `Min` (for example) without having to prefix `Math.`. This works in Mono 3.12.

Actual results:

error CS0138: A `using' directive can only be applied to namespaces but `System.Math' denotes a type. Consider using a `using static' instead

I'm using mono master (bc13a8125e5efe020eafe42560302ff4f42f5557).
Comment 1 Marek Safar 2015-01-30 10:47:30 UTC
The spec has changed, Correct syntax is "using static Foo;"
Comment 2 Sandy Armstrong [MSFT] 2015-01-30 10:59:53 UTC
Mea culpa. I'll go actually learn C# 6 now...
Comment 3 Sandy Armstrong [MSFT] 2015-01-30 11:03:37 UTC
FWIW, `using static System.Math;` is not working in the REPL in master:

csharp> using System.Math;
(1,2): error CS0138: A `using' directive can only be applied to namespaces but `System.Math' denotes a type. Consider using a `using static' instead
/Users/sandy/mono-prefix/lib/mono/4.5/mscorlib.dll (Location of the symbol related to previous error)
csharp> using static System.Math;
(1,7): error CS1525: Unexpected symbol `static', expecting `('
Comment 4 Marek Safar 2015-02-10 04:13:37 UTC
REPL issues is fixed in master