Updates following discussion.

Changelog.md

@@ -18,18 +18,24 @@
 
   These modules are compatible with `base:Data.Char`.
 - Re-export some functions from `Data.Char` in order to make `Unicode.Char`
-  a drop-in replacement.
+  a drop-in replacement in a _future_ version of this package.
 - Drop support for GHC 7.10.3
 
 ### Deprecations
 
-- In `Unicode.Char.General`.
+- In `Unicode.Char.Case`:
 
-  - `isLetter`
-  - `isSpace`
+  - `isUpper`: use `isUpperCase` instead.
+  - `isLower`: use `isLowerCase` instead.
 
-  Preserve the behavior of these functions in `isAlphabetic` and `isWhiteSpace`
-  respectively.
+- In `Unicode.Char.General`:
+
+  - `isLetter`: use `isAlphabetic` instead.
+  - `isSpace`: use `isWhiteSpace` instead.
+
+- In `Unicode.Char`: same as hereinabove. These functions will be replaced in a
+  _future_ release with the functions with the same names from
+  `Unicode.Char.Case.Compat` and `Unicode.Char.General.Compat`.
 
 ## 0.2.0 (November 2021)
 

lib/Unicode/Char.hs

@@ -43,10 +43,10 @@ where
 
 import Data.Char (chr, ord)
 import Data.Version (Version, makeVersion)
-import Unicode.Char.Case hiding (isLower, isUpper)
-import Unicode.Char.Case.Compat
-import Unicode.Char.General hiding (isLetter, isSpace)
-import Unicode.Char.General.Compat
+import Unicode.Char.Case
+import Unicode.Char.Case.Compat hiding (isLower, isUpper)
+import Unicode.Char.General
+import Unicode.Char.General.Compat hiding (isLetter, isSpace)
 import Unicode.Char.Identifiers
 import Unicode.Char.Numeric
 import Unicode.Char.Normalization

lib/Unicode/Char/General.hs

@@ -431,7 +431,9 @@ isSymbol c = case generalCategory c of
     OtherSymbol    -> True
     _              -> False
 
--- | Returns 'True' for alphabetic Unicode characters.
+-- | Returns 'True' for alphabetic Unicode characters (lower-case, upper-case
+-- and title-case letters, plus letters of caseless scripts and modifiers
+-- letters).
 --
 -- @since 0.1.0
 {-# INLINE isLetter #-}

test/Unicode/CharSpec.hs

@@ -7,6 +7,12 @@ module Unicode.CharSpec
 
 import qualified Data.Char as Char
 import qualified Unicode.Char as UChar
+-- [TODO] Remove the following qualified imports once isLetter and isSpace
+--        are removed from Unicode.Char.General
+import qualified Unicode.Char.General.Compat as UCharCompat
+-- [TODO] Remove the following qualified imports once isUpper and isLower
+--        are removed from Unicode.Char.Case
+import qualified Unicode.Char.Case.Compat as UCharCompat
 import Data.Foldable (traverse_)
 import Test.Hspec
 
@@ -45,7 +51,7 @@ spec = do
     it "isControl" do
       UChar.isControl `shouldBeEqualTo` Char.isControl
     it "isLetter" do
-      UChar.isLetter `shouldBeEqualTo` Char.isLetter
+      UCharCompat.isLetter `shouldBeEqualTo` Char.isLetter
     it "isMark" do
       UChar.isMark `shouldBeEqualTo` Char.isMark
     it "isNumber" do
@@ -57,14 +63,14 @@ spec = do
     it "isSeparator" do
       UChar.isSeparator `shouldBeEqualTo` Char.isSeparator
     it "isSpace" do
-      UChar.isSpace `shouldBeEqualTo` Char.isSpace
+      UCharCompat.isSpace `shouldBeEqualTo` Char.isSpace
     it "isSymbol" do
       UChar.isSymbol `shouldBeEqualTo` Char.isSymbol
   describe' "Case" do
     it "isLower" do
-      UChar.isLower `shouldBeEqualTo` Char.isLower
+      UCharCompat.isLower `shouldBeEqualTo` Char.isLower
     it "isUpper" do
-      UChar.isUpper `shouldBeEqualTo` Char.isUpper
+      UCharCompat.isUpper `shouldBeEqualTo` Char.isUpper
     it "toLower" do
       UChar.toLower `shouldBeEqualTo` Char.toLower
     it "toUpper" do