* In GHC 8.4.1, the operator <> has become a method of the Semigroup class
and is exported from the Prelude. This is unfortunate, since <> is also
exported from the standard library module Text.PrettyPrint, so in any
module that defines a pretty printer, there is likely to be an ambiguity.
This affects ~18 modules in GF. Solution:
import Prelude hiding (<>)
This works also in older versions of GHC, since GHC does't complain if
you hide something that doesn't exists.
* In GHC 8.4.1, Semigroup has become a superclass of Monoid. This means
that anywhere you define an instance of the Monoid class you also have to
define an instance in the Semigroup class.
This affects Data.Binary.Builder in GF. Solution: conditionally define
a Semigroup instance if compiling with base>=4.11 (ghc>=8.4.1)
2 modules: Name clashes caused by Applicative-Monad change in Prelude
2 modules: Ambiguities caused by Foldable/Traversable in Prelude
2 modules: Backwards incompatible changes in time-1.5 for defaultTimeLocale
9 modules: {-# LANGUAGE FlexibleContexts #-} (because GHC checks inferred types
now, in addition to explicitly given type signatures)
Also silenced warnings about tab characters in source files.
Included renamings:
SourceGrammar -> Grammar
SourceModule -> Module
SourceModInfo -> ModuleInfo
emptySourceGrammar -> emptyGrammar
Also introduces a type synonym (which might be good to turn into a newtype):
type ModuleName = Ident
The reason is to make types like the following more self documenting:
type Module = (ModuleName,ModuleInfo)
type QIdent = (ModuleName,Ident)
GF.Text.Pretty provides the class Pretty and overloaded versions of the pretty
printing combinators in Text.PrettyPrint, allowing pretty printable values to
be used directly instead of first having to convert them to Doc with functions
like text, int, char and ppIdent. Some modules have been converted to use
GF.Text.Pretty, but not all. Precedences could be added to simplify the pretty
printers for terms and patterns.
GF.Infra.Location contains the types Location and L, factored out from
GF.Grammar.Grammar, and the class HasSourcePath. This allowed the import
of GF.Grammar.Grammar to be removed from GF.Infra.CheckM, making it more
like a pure library module.
PGF exports the public, stable API.
PGF.Internal exports additional things needed in the GF compiler & shell,
including the nonstardard version of Data.Binary.
+ 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 sequence operator (x+y) was implemented by splitting the string to be
matched at all positions and trying to match the parts against the two
subpatterns. To reduce the number of splits, we now estimate the minimum and
maximum length of the string that the subpatterns could match. For common
cases, where one of the subpatterns is a string of known length, like
in (x+"y") or (x + ("a"|"o"|"u"|"e")+"y"), only one split will be tried.
The pretty printer produced
mkDet pre {"a"; "an" / vowel} Sg
which is not accepted by the parser. The parser assigns pre { ... }, to
prededence level 4, and this is now reflected in the pretty printer, so
it prints
mkDet (pre {"a"; "an" / vowel}) Sg
(This caused a problem in GFSE since it parsers pretty printed grammars...)
krangelov