add Proem.Text.fromInt

.gitignore

@@ -1 +1,2 @@
 dist-newstyle/
+Session.vim

bench/Main.hs

@@ -0,0 +1,16 @@
+module Main where
+
+import Data.Text qualified as Text
+import Data.Text.Lazy qualified as Text.Lazy
+import Data.Text.Lazy.Builder qualified as Text.Lazy.Builder
+import Data.Text.Lazy.Builder.Int qualified as Text.Lazy.Builder
+import ParkBench
+import Proem.Text qualified
+
+main :: IO ()
+main = do
+  benchmark
+    [ function "pack . show" (Text.pack . show) (-1000),
+      function "toStrict . toLazyText . decimal" (Text.Lazy.toStrict . Text.Lazy.Builder.toLazyText . Text.Lazy.Builder.decimal) (-1000),
+      function "Proem.Text.fromInt" Proem.Text.fromInt (-1000)
+    ]

proem.cabal

@@ -46,6 +46,7 @@ library
     Proem.File
     Proem.List
     Proem.Seq
+    Proem.Text
   hs-source-dirs: src
   default-language: Haskell2010
   ghc-options:
@@ -63,3 +64,17 @@ library
   if impl(ghc >= 9.2)
     ghc-options:
       -Wno-missing-kind-signatures
+
+benchmark bench
+  build-depends:
+    base,
+    park-bench ^>= 0.1.0,
+    proem,
+    text,
+  default-extensions:
+    ImportQualifiedPost
+  hs-source-dirs: bench
+  default-language: Haskell2010
+  ghc-options: -O -rtsopts -with-rtsopts=-T
+  main-is: Main.hs
+  type: exitcode-stdio-1.0

src/Proem/Text.hs

@@ -0,0 +1,27 @@
+module Proem.Text
+  ( fromInt,
+  )
+where
+
+import Data.Text (Text)
+import qualified Data.Text as Text
+import qualified Data.Text.Lazy as Text.Lazy
+import qualified Data.Text.Lazy.Builder as Text.Lazy.Builder
+import qualified Data.Text.Lazy.Builder.Int as Text.Lazy.Builder
+import Prelude
+
+-- | Construct a text from an int.
+fromInt :: Int -> Text
+fromInt n =
+  -- Benchmarking seems to indicate going through a proper builder becomes faster at 5 characters
+  if n >= 0
+    then if n < 9999 then stringy n else buildery n
+    else if n >= -999 then stringy n else buildery n
+  where
+    stringy :: Int -> Text
+    stringy =
+      Text.pack . show
+
+    buildery :: Int -> Text
+    buildery =
+      Text.Lazy.toStrict . Text.Lazy.Builder.toLazyText . Text.Lazy.Builder.decimal