Blue

A managed C# compiler written in C#.

By Mike Stall

Feb 4, 2005

Blue is a C# compiler written entirely in C# using the .NET. It tagets the V1.0/v1.1 runtimes. The current version does not yet support v2.0 (and is actually very confused when it tries to import generics in v2.0 mscorlib).

It uses Reflection-emit to produce the IL.

Blue is primarily a sample of reflection-emit and not intended as a production compiler.

Usage

You can build Blue.exe via the following command line:

csc /out:blue.exe @blue_source_core

build_all.bat will build Blue.exe from CSC.exe, and then turn around and use blue.exe to compile itself to produce dogfood.exe

Use blue /? for usage details.

Help

bluehelp.xml is the xml-help produced by the /doc csc option.

BlueHelp.chm is a compiled version of bluehelp.xml using the NDoc utility. These help files mostly document implementation details.

NDoc is available at http://ndoc.sourceforge.net/

Use blue /? for usage details.

Missing features

Blue is reasonably complete (it can compile itself), but is still missing some features. This is a partial list of missing features:

• Custom attributes
• unsafe code
• checked/unchecked, locked keyword, using keyword
• floating point, decimal types.
• Multi dimensional arrays. (note that it can handle jagged arrays)
• Some operator overloading. (Allows binary operators like + to be overloaded, doesn't yet handle overloaded type casts, unary ops, or ++/--.)
• Still may assert when compiling an illegal program.

To see further limitations, look at which command line parameters are present in CSC but missing in Blue.