Add isEmpty and deprecate null

CHANGELOG.md

@@ -7,6 +7,7 @@ Notable changes to this project are documented in this file. The format is based
 Breaking changes:
 
 New features:
+- Add `isEmpty` and add deprecation warning for `null` (by @sigma-andex)
 
 Bugfixes:
 

src/Data/String.purs

@@ -6,5 +6,5 @@ module Data.String
 
 import Data.String.CodePoints
 
-import Data.String.Common (joinWith, localeCompare, null, replace, replaceAll, split, toLower, toUpper, trim)
+import Data.String.Common (joinWith, localeCompare, null, isEmpty, replace, replaceAll, split, toLower, toUpper, trim)
 import Data.String.Pattern (Pattern(..), Replacement(..))

src/Data/String/Common.purs

@@ -1,27 +1,39 @@
 module Data.String.Common
-  ( null
+  ( isEmpty
+  , joinWith
   , localeCompare
+  , null
   , replace
   , replaceAll
   , split
   , toLower
   , toUpper
   , trim
-  , joinWith
-  ) where
+  )
+  where
 
 import Prelude
 
 import Data.String.Pattern (Pattern, Replacement)
+import Prim.TypeError (class Warn, Text)
 
--- | Returns `true` if the given string is empty.
+-- | Returns `true` if the given string is empty. Alias for isEmpty.
 -- |
 -- | ```purescript
 -- | null "" == true
 -- | null "Hi" == false
 -- | ```
-null :: String -> Boolean
-null s = s == ""
+null :: Warn (Text "'null' is deprecated, use 'isEmpty'") => String -> Boolean
+null = isEmpty
+
+-- | Returns `true` if the given string is empty.
+-- |
+-- | ```purescript
+-- | isEmpty "" == true
+-- | isEmpty "Hi" == false
+-- | ```
+isEmpty :: String -> Boolean
+isEmpty s = s == ""
 
 -- | Compare two strings in a locale-aware fashion. This is in contrast to
 -- | the `Ord` instance on `String` which treats strings as arrays of code

test/Test/Data/String.purs

@@ -12,9 +12,9 @@ import Test.Assert (assert, assertEqual)
 testString :: Effect Unit
 testString = do
 
-  log "null"
-  assert $ S.null ""
-  assert $ not (S.null "a")
+  log "isEmpty"
+  assert $ S.isEmpty ""
+  assert $ not (S.isEmpty "a")
 
   log "stripPrefix"
   -- this is a re-export from Data.String.CodeUnits, so the majority of tests are in there