This adds:
* a base `README.md` file to `codegen`
* module docstrings for the modules in `generators`
* help strings on all command line flags
Moreover some unneeded command line flags (`--namespace`,
`--include-dir` and `--trap-affix`) have been dropped.
While the (removed) comment is correct and the frontend can be called in
different modes, both `swift build` and `xcodebuild` always use
`-primary-files` when compiling Swift projects.
The other mode was present only within our test runner (`qltest.sh`), so
removing it and doing what the official build systems do simplifies our
code base.
Additionally, file archival is now a separate function/operation.
Python code was simplified, and now a `--generate` option can be used
to drive what can be generated.
The extractor pack creation now will use an internally generated
dbscheme. This should be the same as the checked in one, but doing so
allows `bazel run create-extractor-pack` and `bazel run codegen` to be
run independently from one another, while previously the former had to
follow the latter in case of a schema change. This is the change that
triggered the above simplification, as in order for the two dbscheme
files to be identical, the first `// generated` line had to state the
same generator script.
By explicitly marking children in the `schema.yml` file, an internal
`getAChild` predicate is implemented, that is in turn used in `AstNode`
to implement `getParent`.
This is yet to be used in the control flow library to replace the
hand-rolled implementation.
A further, more complex step is to use the same information to fully
generate the core implementation of `PrintAst` (including the
accessor string). This will be done later.
The `parent` tests use the same swift code as the extractor tests, and
this is currently enforced by `sync-files.py`. Notice that `qltest.sh`
had to be modified to deal with multiple files, which was not working
yet.
While we need universal references to catch different value categories,
we don't need perfect forwarding as `fetchLabel` does not behave
differently on lvalue and rvalues.
That class was meant to allow aggregate initialization of generated
C++ entries having the label `id` as first argument.
As aggregate initialization turned out to be undesirable (names of
fields are not explicit, and `{}` must be inserted for empty
superclasses), this commit removes it and disallows aggregate
initialization altogether by defining empty constructors for generated
classes.
