The XL distribution contains two top-level directories:
To build the XL2 compiler, go to the
xl2 directory and type
% cd xl2 % make
This will perform a compiler bootstrap. In other words, several compilers will be built successively:
xl, written in C++, and compiling a simplified version of XL2
bxl, written in simplified XL and compiled with
xl, and implementing a slightly less simplified version of XL.
bxlcompiles itself several times, resulting in compilers called
nxl, compiled with
bxl, written in bootstrap-level XL, and implementing the full XL2 semantics.
The bootstrapping process is not perfect, because it proved difficult to keep the language compiled by
nxl compatible with the simplified idiom accepted by
bxl. As a result,
nxl can only compile itself with the
-bootstrap option, which make it accept a very sloppy variant of XL2.
To build the XLR compiler, go to the
xlr directory and type
% cd xlr % make % make test
The XLR language is still under active development and may change rapidly.