Implemented convenience functions for Float query parameters.

src/Url/Builder.elm

@@ -1,6 +1,6 @@
 module Url.Builder exposing
   ( absolute, relative, crossOrigin, custom, Root(..)
-  , QueryParameter, string, int, toQuery
+  , QueryParameter, string, int, float, toQuery
   )
 
 
@@ -194,6 +194,20 @@ int key value =
   QueryParameter (Url.percentEncode key) (String.fromInt value)
 
 
+{-| Create a percent-encoded query parameter.
+
+    absolute ["search"] [ float "lat" 48.4428425, float "lng" 1.4812848 ]
+    -- "/search?lat=48.4428425&lng=1.4812848"
+
+Writing `float key n` is the same as writing `string key (String.fromFloat n)`.
+So this is just a convenience function, making your code a bit shorter!
+
+-}
+float : String -> Float -> QueryParameter
+float key value =
+  QueryParameter (Url.percentEncode key) (String.fromFloat value)
+
+
 {-| Convert a list of query parameters to a percent-encoded query. This
 function is used by `absolute`, `relative`, etc.
 

src/Url/Parser/Query.elm

@@ -1,5 +1,5 @@
 module Url.Parser.Query exposing
-  ( Parser, string, int, enum, custom
+  ( Parser, string, int, float, enum, custom
   , map, map2, map3, map4, map5, map6, map7, map8
   )
 
@@ -96,6 +96,34 @@ int key =
         Nothing
 
 
+{-| Handle `Float` parameters.
+
+
+    height : Parser (Maybe Float)
+    height =
+        float "height"
+
+    -- ?height=2               == Just 2
+    -- ?height=17.876          == Just 17.876
+    -- ?height=two             == Nothing
+    -- ?sort=date              == Nothing
+    -- ?height=1.2&height=3.19 == Nothing
+
+Check out [`custom`](#custom) if you need to handle multiple `height` parameters.
+
+-}
+float : String -> Parser (Maybe Float)
+float key =
+    custom key <|
+        \stringList ->
+            case stringList of
+                [ str ] ->
+                    String.toFloat str
+
+                _ ->
+                    Nothing
+
+
 {-| Handle enumerated parameters. Maybe you want a true-or-false parameter:
 
     import Dict