+ Generalize the CommandInfo type by parameterizing it on the monad
instead of just the environment.
+ Generalize the commands defined in
GF.Command.{Commands,Commands2,CommonCommands,SourceCommands,HelpCommand}
to work in any monad that supports the needed operations.
+ Liberate GF.Command.Interpreter from the IO monad.
Also, move the current PGF from CommandEnv to GFEnv in
GF.Interactive, making the command interpreter even more generic.
+ Use a state monad to maintain the state of the interpreter in
GF.{Interactive,Interactive2}.
Some C run-time functionality is now available in the GF shell, by starting
GF with 'gf -cshell' or 'gf -crun'. Only limited functionality is available
when running the shell in these modes:
- You can only import .pgf files, not source files.
- The -retain flag can not be used and the commands that require it to work
are not available.
- Only 18 of the 40 commands available in the usual shell have been
implemented. The 'linearize' and 'parse' commands are the only ones
that call the C run-time system, and they support only a limited set of
options and flags. Use the 'help' commmands for details.
- A new command 'generate_all', that calls PGF2.generateAll, has been added.
Unfortuntaly, using it causes 'segmentation fault'.
This is implemented by adding two new modules: GF.Command.Commands2 and
GF.Interactive2. They are copied and modified versions of GF.Command.Commands
and GF.Interactive, respectively. Code for unimplemented commands and other
code that has not been adapted to the C run-time system has been left in
place, but commented out, pending further work.
Because the prompt included the name of the abstract syntax, the loading
of the PGF was forced even if -retain was used. Even worse,
if an error occured while loading the PGF, it was repeated and caught
every time the prompt was printed, creating an infite loop. The solution
is to not print the name of the abstract syntax when the grammar is
imported with -retain, which is the way things were before anyway.
The commands available in the shell after import -retain are now a superset
of the commands available after import without -retain.
The PGF is created lazily, so there should be no performance penalty if
the PGF isn't needed. If there are errors, they won't be reported until a
command that uses the PGF is entered.
+ References to modules under src/compiler have been eliminated from the PGF
library (under src/runtime/haskell). Only two functions had to be moved (from
GF.Data.Utilities to PGF.Utilities) to make this possible, other apparent
dependencies turned out to be vacuous.
+ In gf.cabal, the GF executable no longer directly depends on the PGF library
source directory, but only on the exposed library modules. This means that
there is less duplication in gf.cabal and that the 30 modules in the
PGF library will no longer be compiled twice while building GF.
To make this possible, additional PGF library modules have been exposed, even
though they should probably be considered for internal use only. They could
be collected in a PGF.Internal module, or marked as "unstable", to make
this explicit.
+ Also, by using the -fwarn-unused-imports flag, ~220 redundant imports were
found and removed, reducing the total number of imports by ~15%.
The SIO monad is a restriction of the IO monad with two purposes:
+ Access to arbitrary IO operations can be turned off by setting the environment
variable GF_RESTRICTED. There is a limited set of IO operations that are
considered safe and always allowed.
+ It allows output to stdout to be captured. This can be used in gf -server
mode, where output of GF shell commands is made part of HTTP responses
returned to clients.
