add support for numbers in scientific notation

Author: gvolpe

data/scientific-notation.settings

@@ -0,0 +1,4 @@
+[com/github/wwmm/easyeffects/streamoutputs/bassenhancer]
+amount=-6.9388939039072284e-16
+blend=0.0
+listen=true

output/scientific-notation.nix

@@ -0,0 +1,15 @@
+# Generated via dconf2nix: https://github.com/gvolpe/dconf2nix
+{ lib, ... }:
+
+with lib.hm.gvariant;
+
+{
+  dconf.settings = {
+    "com/github/wwmm/easyeffects/streamoutputs/bassenhancer" = {
+      amount = -6.938893903907228e-16;
+      blend = 0.0;
+      listen = true;
+    };
+
+  };
+}

src/DConf.hs

@@ -21,7 +21,7 @@ vDouble = try $ do
   s <- option "" $ string "-"
   n <- many1 digit
   d <- string "."
-  e <- many1 digit
+  e <- many1 (digit <|> oneOf "eEdD-")
   pure . D $ read (s <> n <> d <> e)
 
 vInt :: Parsec Text () Value

test/DConf2NixTest.hs

@@ -106,5 +106,15 @@ dconf2nixKeybindings =
 prop_dconf2nix_keybindings :: Property
 prop_dconf2nix_keybindings = withTests (10 :: TestLimit) dconf2nixKeybindings
 
+dconf2nixScientificNotation :: Property
+dconf2nixScientificNotation =
+  let input  = "data/scientific-notation.settings"
+      output = "output/scientific-notation.nix"
+      root   = Root T.empty
+  in  baseProperty input output root
+
+prop_dconf2nix_scientific_notation :: Property
+prop_dconf2nix_scientific_notation = withTests (10 :: TestLimit) dconf2nixScientificNotation
+
 dconf2nixTests :: Group
 dconf2nixTests = $$(discover)