Added more format specifiers

src/Turtle/Format.hs

@@ -6,31 +6,34 @@
     Example use of this module:
 
 >>> :set -XOverloadedStrings
->>> import Turtle
+>>> import Turtle.Format
 >>> format ("This is a "%s%" string that takes "%d%" arguments") "format" 2
 "This is a format string that takes 2 arguments"
 
     A `Format` string that takes no arguments has this type:
 
 > "I take 0 arguments" :: Format r r
->
-> format "I take 0 arguments" :: Text
+
+>>> format "I take 0 arguments" :: Text
+"I take 0 arguments"
 
     A `Format` string that takes one argument has this type:
 
 > "I take "%d%" arguments" :: Format r (Int -> r)
 >
 > format ("I take "%d%" argument") :: Int -> Text
->
-> format ("I take "%d%" argument") 1 :: Text
+
+>>> format ("I take "%d%" argument") 1 :: Text
+"I take 1 argument"
 
     A `Format` string that takes two arguments has this type:
 
 > "I "%s%" "%d%" arguments" :: Format r (Text -> Int -> r)
 >
 > format ("I "%s%" "%d%" arguments") :: Text -> Int -> Text
->
-> format ("I "%s%" "%d%" arguments") "take" 2 :: Text
+
+>>> format ("I "%s%" "%d%" arguments") "take" 2 :: Text
+"I take 2 arguments"
 -}
 
 {-# LANGUAGE TypeFamilies #-}
@@ -46,7 +49,11 @@ module Turtle.Format (
     , w
     , d
     , u
+    , o
+    , x
     , f
+    , e
+    , g
     , s
     ) where
 
@@ -55,6 +62,7 @@ import Data.Monoid ((<>))
 import Data.String (IsString(..))
 import Data.Text (Text, pack)
 import Data.Word (Word)
+import Numeric (showEFloat, showFFloat, showGFloat, showHex, showOct)
 import Prelude hiding ((.), id, FilePath)
 
 -- | A `Format` string
@@ -85,22 +93,82 @@ format fmt = fmt >>- id
 makeFormat :: (a -> Text) -> Format r (a -> r)
 makeFormat k = Format (\return_ -> \a -> return_ (k a))
 
--- | `Format` string that inserts any `Show`able value
+{-| `Format` any `Show`able value
+
+>>> format w True
+"True"
+-}
 w :: Show a => Format r (a -> r)
 w = makeFormat (pack . show)
 
--- | `Format` string that inserts an `Int` value
+{-| `Format` an `Int` value as a signed decimal
+
+>>> format d 25
+"25"
+>>> format d (-25)
+"-25"
+-}
 d :: Format r (Int -> r)
 d = w
 
--- | `Format` string that inserts a `Word` value
+{-| `Format` a `Word` value as an unsigned decimal
+
+>>> format u 25
+"25"
+-}
 u :: Format r (Word -> r)
 u = w
 
--- | `Format` string that inserts a `Double`
-f :: Format r (Double -> r)
-f = w
+{-| `Format` a `Word` value as an unsigned octal number
 
--- | `Format` string that inserts `Text`
+>>> format o 25
+"31"
+-}
+o :: Format r (Word -> r)
+o = makeFormat (\n -> pack (showOct n ""))
+
+{-| `Format` a `Word` value as an unsigned hexadecimal number (without a
+    leading \"0x\")
+
+>>> format x 25
+"19"
+-}
+x :: Format r (Word -> r)
+x = makeFormat (\n -> pack (showHex n ""))
+
+{-| `Format` a `Double` using decimal notation with 6 digits of precision
+
+>>> format f 25.1
+"25.100000"
+-}
+f :: Format r (Double -> r)
+f = makeFormat (\n -> pack (showFFloat (Just 6) n ""))
+
+{-| `Format` a `Double` using scientific notation with 6 digits of precision
+
+>>> format e 25.1
+"2.510000e1"
+-}
+e :: Format r (Double -> r)
+e = makeFormat (\n -> pack (showEFloat (Just 6) n ""))
+
+{-| `Format` a `Double` using decimal notation for small exponents and
+    scientific notation for large exponents
+
+>>> format g 25.1
+"25.100000"
+>>> format g 123456789
+"1.234568e8"
+>>> format g 0.00000000001
+"1.000000e-11"
+-}
+g :: Format r (Double -> r)
+g = makeFormat (\n -> pack (showGFloat (Just 6) n ""))
+
+{-| `Format` that inserts `Text`
+
+>>> format s "ABC"
+"ABC"
+-}
 s :: Format r (Text -> r)
 s = makeFormat id

test/Main.hs

@@ -3,4 +3,4 @@ module Main where
 import Test.DocTest
 
 main :: IO ()
-main = doctest ["src/Turtle/Pattern.hs"]
+main = doctest ["src/Turtle/Pattern.hs", "src/Turtle/Format.hs"]