The matchPrefix function is used in str2strings and the partial evaluator to
compute pre{...} tokens. But unlike the description in the GF book and
the implementation in the run-time system, matchPrefix looked at
the concatenation(!) of all following tokens and not just the next token
when deciding how to compute a pre{...} token.
This is a backwards incompatible change, but it is subtle and probably won't
cause any problems. In particular, the example grammars are unaffected.
These changes are inspired by the gf -cshell implementation of these commands.
The output of the linearize command has been changed to remove superfluous
blank lines and commas, and deliver the result as a list of strings instead of
a single multi-line string. This makes it possible to use -all and pipe the
results to the parse command. This also means that with -treebank -all,
the language tag will be repeated for each result from the same language.
The parse command, when trying to parse with more than one language, would
"forget" other results after a failed parse, and thus not send all
successful parses through the pipe. For example, if English is not the first
language in the grammar,
p "hello" | l
would output nothing, instead of translations of "hello" to all languages,
forcing the user to write
p -lang=Eng "hello" | l
instead, to get the expected result. The cause of this behaviour was in the
function fromParse, which was rather messy, so I assume it is not intentional,
but the result of a programming mistake at some point.
The fromParse function has now been refactored from a big recursive function
into
fromParse opts = foldr (joinPiped . fromParse1 opts) void
where the helper functions fromParse1 deals with a single parse result and
joinPiped combines multiple parse results.
+ 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}.
* The following modules are no longer used and have been removed completely:
GF.Compile.Compute.ConcreteLazy
GF.Compile.Compute.ConcreteStrict
GF.Compile.Refresh
* The STM monad has been commented out. It was only used in
GF.Compile.SubExpOpt, where could be replaced with a plain State monad,
since no error handling was needed. One of the functions was hardwired to
the Err monad, but did in fact not use error handling, so it was turned
into a pure function.
* The function errVal has been renamed to fromErr (since it is analogous to
fromMaybe).
* Replaced 'fail' with 'raise' and 'return ()' with 'done' in a few places.
* Some additional old code that was already commented out has been removed.
+ Eliminated vairous ad-hoc coersion functions between specific monads
(IO, Err, IOE, Check) in favor of more general lifting functions
(liftIO, liftErr).
+ Generalized many basic monadic operations from specific monads to
arbitrary monads in the appropriate class (MonadIO and/or ErrorMonad),
thereby completely eliminating the need for lifting functions in lots
of places.
This can be considered a small step forward towards a cleaner
compiler API and more malleable compiler code in general.
+ 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%.
In GF.Compile.CheckGrammar, use a new topological sorting function that
groups independent judgements, allowing them all to be checked before
continuing or reporting errors.
