Evergreen is a sandbox for exploring source-to-source compiler construction with Go.
Be sure to set GOPATH to this directory. If using bash:
export GOPATH=`pwd`
Development workflow is assisted by a binary called "workflow". Evergreen generates parts of itself. You need to build workflow to get started.
go install evergreen/cmd/workflow
Regenerate into src/generated and run tests:
./bin/workflow test
Files in src/generated are only used for testing and will not affect the main build. This will help sanity check your changes to *.dub files. If things look OK, regenerate into src/evergreen:
./bin/workflow build
This command will compile the current program to bin/regenerate before replacing the generated source files. This is a safety net that lets generated sources be updated even when the source code is in an intermediate, uncompilable state. If you need to regenerate sources while the compiler is broken:
./bin/workflow sync
This development loop should help minimize situations where work in progress is lost because changes to the parser break it and prevent it from regenerating itself. This is still a risk, however, so be careful.
- /dubsrc/ contains the DSL sources.
- /src/ contains the Go sources.
- /src/.../generated_dub.go are generated files that have been checked in.
- /src/generated/ contains a temporary copy of the generated sources for testing.
- /output/ is a temporary directory for visualization and debugging information.
- text: source code.
- tree: abstract syntax tree.
- flow: a graph based IR.
An agressive source-to-source compiler will go all the way down and back up this stack:
text => tree => flow => flow => tree => text
Simpler source-to-source compilers will skip many of these stages, trading away the ability to do deeper transformations for simplicity:
text => tree => text