Adding the converted version of booc.

[masonwheeler]

Converted booc from C# to Boo.

[drslump]

In order to make the compiler self hosted we need a bootstrapping compiler, which can simply be a previous binary build of it. I think that before starting to merge the port into the main repository we need to adapt the build system to take this into account so that instead of adding new code to the project we actually replace the old one at the same time.

[masonwheeler]

What sort of changes are needed? All of the code compiles under the current (0.9.5) Boo compiler.

[drslump]

Ideally we should be able to do a checkout of the repository on a brand new computer and just by doing nant build the latest version of the compiler should be generated. By default in .Net we have a C# compiler, which allows to bootstrap the project because the core of Boo is written in that language. Once we start implementing the core in Boo itself we need a Boo bootstraping compiler, something to convert the Boo source code into its runnable form (the assembly).

There are different approaches to solve this issue, some compilers have a specific bootstrapping compiler implemented in a different language (i.e. C) that is able enough to build a version of the target compiler which in turn is used to build the rest of the project. However, since in .Net the binary assemblies are portable, perhaps the easier solution is to include the assemblies for the current compiler and use to bootstrap the compilation of the project.

In essence this should be the flow of the build process:

• Use bootstrapping compiler to generate the compiler core
• Use newly generated compiler core to build the rest of the project

So by including a minimum version of the Boo compiler in its binary form (.Net/mono runnable) on the repository, we can use it to build the compiler .boo sources with the only requirement to have a working .Net environment. That's a cleaner solution in my opinion that keeping the current C# sources in the repository just for bootstrapping purposes.

[masonwheeler]

The existing C# source should probably be kept around (in a separate section of the repository) for verifiability purposes, (Trusting Trust etc,) but yes, that's basically what I had in mind: use binaries of the current compiler as our bootstrapping compiler.