New narrow, widen, signed, and unsigned functions

.stylish-haskell.yaml

@@ -0,0 +1,189 @@
+# stylish-haskell configuration file
+# ==================================
+
+# The stylish-haskell tool is mainly configured by specifying steps. These steps
+# are a list, so they have an order, and one specific step may appear more than
+# once (if needed). Each file is processed by these steps in the given order.
+steps:
+  # Convert some ASCII sequences to their Unicode equivalents. This is disabled
+  # by default.
+  # - unicode_syntax:
+  #     # In order to make this work, we also need to insert the UnicodeSyntax
+  #     # language pragma. If this flag is set to true, we insert it when it's
+  #     # not already present. You may want to disable it if you configure
+  #     # language extensions using some other method than pragmas. Default:
+  #     # true.
+  #     add_language_pragma: true
+
+  # Align the right hand side of some elements.  This is quite conservative
+  # and only applies to statements where each element occupies a single
+  # line.
+  - simple_align:
+      cases: true
+      top_level_patterns: true
+      records: true
+
+  # Import cleanup
+  - imports:
+      # There are different ways we can align names and lists.
+      #
+      # - global: Align the import names and import list throughout the entire
+      #   file.
+      #
+      # - file: Like global, but don't add padding when there are no qualified
+      #   imports in the file.
+      #
+      # - group: Only align the imports per group (a group is formed by adjacent
+      #   import lines).
+      #
+      # - none: Do not perform any alignment.
+      #
+      # Default: global.
+      align: group
+
+      # Folowing options affect only import list alignment.
+      #
+      # List align has following options:
+      #
+      # - after_alias: Import list is aligned with end of import including
+      #   'as' and 'hiding' keywords.
+      #
+      #   > import qualified Data.List      as List (concat, foldl, foldr, head,
+      #   >                                          init, last, length)
+      #
+      # - with_alias: Import list is aligned with start of alias or hiding.
+      #
+      #   > import qualified Data.List      as List (concat, foldl, foldr, head,
+      #   >                                 init, last, length)
+      #
+      # - new_line: Import list starts always on new line.
+      #
+      #   > import qualified Data.List      as List
+      #   >     (concat, foldl, foldr, head, init, last, length)
+      #
+      # Default: after_alias
+      list_align: after_alias
+
+      # Long list align style takes effect when import is too long. This is
+      # determined by 'columns' setting.
+      #
+      # - inline: This option will put as much specs on same line as possible.
+      #
+      # - new_line: Import list will start on new line.
+      #
+      # - new_line_multiline: Import list will start on new line when it's
+      #   short enough to fit to single line. Otherwise it'll be multiline.
+      #
+      # - multiline: One line per import list entry.
+      #   Type with contructor list acts like single import.
+      #
+      #   > import qualified Data.Map as M
+      #   >     ( empty
+      #   >     , singleton
+      #   >     , ...
+      #   >     , delete
+      #   >     )
+      #
+      # Default: inline
+      long_list_align: inline
+
+      # Align empty list (importing instances)
+      #
+      # Empty list align has following options
+      #
+      # - inherit: inherit list_align setting
+      #
+      # - right_after: () is right after the module name:
+      #
+      #   > import Vector.Instances ()
+      #
+      # Default: inherit
+      empty_list_align: inherit
+
+      # List padding determines indentation of import list on lines after import.
+      # This option affects 'long_list_align'.
+      #
+      # - <integer>: constant value
+      #
+      # - module_name: align under start of module name.
+      #   Useful for 'file' and 'group' align settings.
+      list_padding: 4
+
+      # Separate lists option affects formating of import list for type
+      # or class. The only difference is single space between type and list
+      # of constructors, selectors and class functions.
+      #
+      # - true: There is single space between Foldable type and list of it's
+      #   functions.
+      #
+      #   > import Data.Foldable (Foldable (fold, foldl, foldMap))
+      #
+      # - false: There is no space between Foldable type and list of it's
+      #   functions.
+      #
+      #   > import Data.Foldable (Foldable(fold, foldl, foldMap))
+      #
+      # Default: true
+      separate_lists: true
+
+  # Language pragmas
+  - language_pragmas:
+      # We can generate different styles of language pragma lists.
+      #
+      # - vertical: Vertical-spaced language pragmas, one per line.
+      #
+      # - compact: A more compact style.
+      #
+      # - compact_line: Similar to compact, but wrap each line with
+      #   `{-#LANGUAGE #-}'.
+      #
+      # Default: vertical.
+      style: vertical
+
+      # Align affects alignment of closing pragma brackets.
+      #
+      # - true: Brackets are aligned in same collumn.
+      #
+      # - false: Brackets are not aligned together. There is only one space
+      #   between actual import and closing bracket.
+      #
+      # Default: true
+      align: true
+
+      # stylish-haskell can detect redundancy of some language pragmas. If this
+      # is set to true, it will remove those redundant pragmas. Default: true.
+      remove_redundant: true
+
+  # Replace tabs by spaces. This is disabled by default.
+  # - tabs:
+  #     # Number of spaces to use for each tab. Default: 8, as specified by the
+  #     # Haskell report.
+  #     spaces: 8
+
+  # Remove trailing whitespace
+  - trailing_whitespace: {}
+
+# A common setting is the number of columns (parts of) code will be wrapped
+# to. Different steps take this into account. Default: 80.
+columns: 800
+
+# By default, line endings are converted according to the OS. You can override
+# preferred format here.
+#
+# - native: Native newline format. CRLF on Windows, LF on other OSes.
+#
+# - lf: Convert to LF ("\n").
+#
+# - crlf: Convert to CRLF ("\r\n").
+#
+# Default: native.
+newline: native
+
+# Sometimes, language extensions are specified in a cabal file or from the
+# command line instead of using language pragmas in the file. stylish-haskell
+# needs to be aware of these, so it can parse the file correctly.
+#
+# No language extensions are enabled by default.
+# language_extensions:
+  # - TemplateHaskell
+  # - QuasiQuotes

hw-int.cabal

@@ -45,6 +45,8 @@ library
                         HaskellWorks.Data.Int.Narrow.Narrow32
                         HaskellWorks.Data.Int.Narrow.Narrow64
                         HaskellWorks.Data.Int.Narrow.Narrow8
+                        HaskellWorks.Data.Int.Signed
+                        HaskellWorks.Data.Int.Unsigned
                         HaskellWorks.Data.Int.Widen
                         HaskellWorks.Data.Int.Widen.Widen16
                         HaskellWorks.Data.Int.Widen.Widen32

src/HaskellWorks/Data/Int/Narrow.hs

@@ -1,8 +1,102 @@
+{-# LANGUAGE MultiParamTypeClasses #-}
+
 module HaskellWorks.Data.Int.Narrow
   ( module X
+  , Narrow(..)
   ) where
 
-import HaskellWorks.Data.Int.Narrow.Narrow8   as X
-import HaskellWorks.Data.Int.Narrow.Narrow16  as X
-import HaskellWorks.Data.Int.Narrow.Narrow32  as X
-import HaskellWorks.Data.Int.Narrow.Narrow64  as X
+import Data.Int
+import Data.Word
+
+import HaskellWorks.Data.Int.Narrow.Narrow16 as X
+import HaskellWorks.Data.Int.Narrow.Narrow32 as X
+import HaskellWorks.Data.Int.Narrow.Narrow64 as X
+import HaskellWorks.Data.Int.Narrow.Narrow8  as X
+
+class Narrow a b where
+  -- | Cast the value to a smaller size.
+  --
+  -- If the value does not fit in the smaller size, data will be lost.
+  --
+  -- This gives a better indication of intent than `Prelude.fromIntegral'.
+  narrow :: a -> b
+
+instance Narrow Int8 Int8 where
+  narrow = id
+  {-# INLINE narrow #-}
+
+instance Narrow Int16 Int8 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Int32 Int8 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Int64 Int8 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Int16 Int16 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Int32 Int16 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Int64 Int16 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Int32 Int32 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Int64 Int32 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Int64 Int64 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Word8 Word8 where
+  narrow = id
+  {-# INLINE narrow #-}
+
+instance Narrow Word16 Word8 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Word32 Word8 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Word64 Word8 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Word16 Word16 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Word32 Word16 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Word64 Word16 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Word32 Word32 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Word64 Word32 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}
+
+instance Narrow Word64 Word64 where
+  narrow = fromIntegral
+  {-# INLINE narrow #-}

src/HaskellWorks/Data/Int/Signed.hs

@@ -0,0 +1,40 @@
+{-# LANGUAGE TypeFamilies #-}
+
+module HaskellWorks.Data.Int.Signed
+  ( Signed(..)
+  ) where
+
+import Data.Int
+import Data.Word
+
+class Signed a where
+  type SignedOf a
+
+  -- | Cast the value to a larger size.
+  --
+  -- This is safer to use than 'Prelude.fromIntegral'.
+  signed :: a -> SignedOf a
+
+instance Signed Word8 where
+  type SignedOf Word8 = Int8
+
+  signed = fromIntegral
+  {-# INLINE signed #-}
+
+instance Signed Word16 where
+  type SignedOf Word16 = Int16
+
+  signed = fromIntegral
+  {-# INLINE signed #-}
+
+instance Signed Word32 where
+  type SignedOf Word32 = Int32
+
+  signed = fromIntegral
+  {-# INLINE signed #-}
+
+instance Signed Word64 where
+  type SignedOf Word64 = Int64
+
+  signed = fromIntegral
+  {-# INLINE signed #-}

src/HaskellWorks/Data/Int/Unsigned.hs

@@ -0,0 +1,40 @@
+{-# LANGUAGE TypeFamilies #-}
+
+module HaskellWorks.Data.Int.Unsigned
+  ( Unsigned(..)
+  ) where
+
+import Data.Int
+import Data.Word
+
+class Unsigned a where
+  type UnsignedOf a
+
+  -- | Cast the value to a larger size.
+  --
+  -- This is safer to use than 'Prelude.fromIntegral'.
+  unsigned :: a -> UnsignedOf a
+
+instance Unsigned Int8 where
+  type UnsignedOf Int8 = Word8
+
+  unsigned = fromIntegral
+  {-# INLINE unsigned #-}
+
+instance Unsigned Int16 where
+  type UnsignedOf Int16 = Word16
+
+  unsigned = fromIntegral
+  {-# INLINE unsigned #-}
+
+instance Unsigned Int32 where
+  type UnsignedOf Int32 = Word32
+
+  unsigned = fromIntegral
+  {-# INLINE unsigned #-}
+
+instance Unsigned Int64 where
+  type UnsignedOf Int64 = Word64
+
+  unsigned = fromIntegral
+  {-# INLINE unsigned #-}