import xml

JSON/renderAs.dhall

@@ -164,8 +164,6 @@
 
   let Format =
           ./Format.dhall
-            sha256:d7936b510cfc091faa994652af0eb5feb889cd44bc989edbe4f1eb8c5623caac
-        ? ./Format.dhall
 
   let ObjectField = { mapKey : Text, mapValue : Block }
 

Location/Type.dhall

@@ -5,9 +5,7 @@ let Location
 
 let example0 =
         assert
-      :     missing
-              sha256:f428188ff9d77ea15bc2bcd0da3f8ed81b304e175b07ade42a3b0fb02941b2aa as Location
-          ? missing as Location
+      :     missing as Location
         ≡ < Environment : Text
           | Local : Text
           | Missing

XML/Type.dhall

@@ -0,0 +1,65 @@
+{-|
+Dhall encoding of an arbitrary XML element
+
+For example, the following XML element:
+
+```
+<foo n="1"><bar>baz</bar></foo>
+```
+
+... corresponds to the following Dhall expression:
+
+
+```
+λ(XML : Type)
+ → λ ( xml
+     : { text :
+           Text → XML
+       , rawText :
+           Text → XML
+       , element :
+             { attributes :
+                 List { mapKey : Text, mapValue : Text }
+             , content :
+                 List XML
+             , name :
+                 Text
+             }
+           → XML
+       }
+     )
+ → xml.element
+   { attributes =
+       [ { mapKey = "n", mapValue = "1" } ]
+   , content =
+       [ xml.element
+         { attributes =
+             [] : List { mapKey : Text, mapValue : Text }
+         , content =
+             [ xml.text "baz" ]
+         , name =
+             "bar"
+         }
+       ]
+   , name =
+       "foo"
+   }
+```
+-}
+let XML/Type
+    : Type
+    = ∀(XML : Type) →
+      ∀ ( xml
+        : { text : Text → XML
+          , rawText : Text → XML
+          , element :
+              { attributes : List { mapKey : Text, mapValue : Text }
+              , content : List XML
+              , name : Text
+              } →
+                XML
+          }
+        ) →
+        XML
+
+in  XML/Type

XML/attribute.dhall

@@ -0,0 +1,6 @@
+--| Builds a key-value record with a Text key and value.
+let attribute
+    : Text → Text → { mapKey : Text, mapValue : Text }
+    = λ(key : Text) → λ(value : Text) → { mapKey = key, mapValue = value }
+
+in  attribute

XML/element.dhall

@@ -0,0 +1,55 @@
+{-|
+Create an XML element value.
+
+```
+let XML = ./package.dhall
+
+in  XML.render
+    ( XML.element
+      { name = "foo"
+      , attributes = XML.emptyAttributes
+      , content =
+          [ XML.leaf { name = "bar", attributes = [ XML.attribute "n" "1" ] }
+          , XML.leaf { name = "baz", attributes = [ XML.attribute "n" "2" ] }
+          ]
+      }
+    )
+
+= "<foo><bar n=\"1\"/><baz n=\"2\"/></foo>"
+```
+-}
+let XML =
+        ./Type.dhall
+
+let List/map =
+        ../List/map.dhall
+
+let Args =
+        { attributes : List { mapKey : Text, mapValue : Text }
+        , name : Text
+        , content : List XML
+        }
+      : Type
+
+let element
+    : Args → XML
+    = λ(elem : Args) →
+      λ(XML : Type) →
+      λ ( xml
+        : { text : Text → XML
+          , rawText : Text → XML
+          , element :
+              { attributes : List { mapKey : Text, mapValue : Text }
+              , content : List XML
+              , name : Text
+              } →
+                XML
+          }
+        ) →
+        xml.element
+          { attributes = elem.attributes
+          , name = elem.name
+          , content = List/map XML@1 XML (λ(x : XML@1) → x XML xml) elem.content
+          }
+
+in  element

XML/emptyAttributes.dhall

@@ -0,0 +1,2 @@
+--| Create an empty XML attribute List.
+[] : List { mapKey : Text, mapValue : Text }

XML/leaf.dhall

@@ -0,0 +1,26 @@
+{-|
+Create an XML element value without child elements.
+
+```
+let XML = ./package.dhall
+
+in  XML.render (XML.leaf { name = "foobar", attributes = XML.emptyAttributes })
+
+= "<foobar/>"
+```
+-}
+let XML =
+        ./Type.dhall
+
+let element =
+        ./element.dhall
+
+let leaf
+    : { attributes : List { mapKey : Text, mapValue : Text }, name : Text } →
+        XML
+    = λ ( elem
+        : { attributes : List { mapKey : Text, mapValue : Text }, name : Text }
+        ) →
+        element (elem ⫽ { content = [] : List XML })
+
+in  leaf

XML/package.dhall

@@ -0,0 +1,17 @@
+{ Type =
+      ./Type.dhall
+, attribute =
+      ./attribute.dhall
+, render =
+      ./render.dhall
+, element =
+      ./element.dhall
+, leaf =
+      ./leaf.dhall
+, text =
+      ./text.dhall
+, rawText =
+      ./rawText.dhall
+, emptyAttributes =
+      ./emptyAttributes.dhall
+}

XML/rawText.dhall

@@ -0,0 +1,38 @@
+{-|
+Create a Text value to be inserted into an XML element as content with no
+character escaping.
+
+```
+let XML = ./package.dhall
+
+in  XML.render
+    ( XML.element
+      { name = "location"
+      , attributes = XML.emptyAttributes
+      , content = [ XML.rawText "<bar n=\"1\"/>" ]
+      }
+    )
+= "<foo><bar n=\"1\"/></foo>"
+```
+-}
+let XML =
+        ./Type.dhall
+
+let rawText
+    : Text → XML
+    = λ(d : Text) →
+      λ(XML : Type) →
+      λ ( xml
+        : { text : Text → XML
+          , rawText : Text → XML
+          , element :
+              { attributes : List { mapKey : Text, mapValue : Text }
+              , content : List XML
+              , name : Text
+              } →
+                XML
+          }
+        ) →
+        xml.rawText d
+
+in  rawText

XML/render.dhall

@@ -0,0 +1,128 @@
+{-|
+Render an `XML` value as `Text`
+
+For indentation and schema validation, see the `xmllint` utility
+bundled with libxml2.
+
+```
+let XML = ./package.dhall
+
+in  XML.render
+    ( XML.element
+      { name = "foo"
+      , attributes = [ XML.attribute "a" "x", XML.attribute "b" (Natural/show 2) ]
+      , content = [ XML.leaf { name = "bar", attributes = XML.emptyAttributes } ]
+      }
+    )
+= "<foo a=\"x\" b=\"2\"><bar/></foo>"
+```
+
+-}
+let XML =
+        ./Type.dhall
+
+let Text/concatMap =
+        ../Text/concatMap.dhall
+
+let Text/concat =
+        ../Text/concat.dhall
+
+let element =
+        ./element.dhall
+
+let text =
+        ./text.dhall
+
+let emptyAttributes =
+        ./emptyAttributes.dhall
+
+let Attr = { mapKey : Text, mapValue : Text }
+
+let esc = λ(x : Text) → λ(y : Text) → Text/replace x "&${y};"
+
+let `escape&` = esc "&" "amp"
+
+let `escape<` = esc "<" "lt"
+
+let `escape>` = esc ">" "gt"
+
+let `escape'` = esc "'" "apos"
+
+let `escape"` = esc "\"" "quot"
+
+let escapeCommon = λ(text : Text) → `escape<` (`escape&` text)
+
+let escapeAttr = λ(text : Text) → `escape"` (`escape'` (escapeCommon text))
+
+let escapeText = λ(text : Text) → `escape>` (escapeCommon text)
+
+let renderAttr = λ(x : Attr) → " ${x.mapKey}=\"${escapeAttr x.mapValue}\""
+
+let render
+    : XML → Text
+    = λ(x : XML) →
+        x
+          Text
+          { text = escapeText
+          , rawText = λ(t : Text) → t
+          , element =
+              λ ( elem
+                : { attributes : List { mapKey : Text, mapValue : Text }
+                  , content : List Text
+                  , name : Text
+                  }
+                ) →
+                let attribs = Text/concatMap Attr renderAttr elem.attributes
+
+                in      "<${elem.name}${attribs}"
+                    ++  ( if    Natural/isZero (List/length Text elem.content)
+                          then  "/>"
+                          else  ">${Text/concat elem.content}</${elem.name}>"
+                        )
+          }
+
+let simple =
+      λ(name : Text) →
+      λ(content : List XML) →
+        element { name, attributes = emptyAttributes, content }
+
+let example0 =
+        assert
+      :   render
+            ( simple
+                "note"
+                [ simple "to" [ text "Tove" ]
+                , simple "from" [ text "Jani" ]
+                , simple "heading" [ text "Reminder" ]
+                , simple "body" [ text "Don't forget me this weekend!" ]
+                ]
+            )
+        ≡ Text/replace
+            "\n"
+            ""
+            ''
+            <note>
+            <to>Tove</to>
+            <from>Jani</from>
+            <heading>Reminder</heading>
+            <body>Don't forget me this weekend!</body>
+            </note>
+            ''
+
+let example1 =
+        assert
+      :   render
+            ( element
+                { name = "escape"
+                , attributes = toMap { attribute = "<>'\"&" }
+                , content = [ text "<>'\"&" ]
+                }
+            )
+        ≡ Text/replace
+            "\n"
+            ""
+            ''
+            <escape attribute="&lt;>&apos;&quot;&amp;">&lt;&gt;'"&amp;</escape>
+            ''
+
+in  render

XML/text.dhall

@@ -0,0 +1,37 @@
+{-|
+Create a Text value to be inserted into an XML element as content.
+
+```
+let XML = ./package.dhall
+
+in  XML.render
+    ( XML.element
+      { name = "location"
+      , attributes = XML.emptyAttributes
+      , content = [ XML.text "/foo/bar" ]
+      }
+    )
+= "<location>/foo/bar</location>"
+```
+-}
+let XML =
+        ./Type.dhall
+
+let text
+    : Text → XML
+    = λ(d : Text) →
+      λ(XML : Type) →
+      λ ( xml
+        : { text : Text → XML
+          , rawText : Text → XML
+          , element :
+              { attributes : List { mapKey : Text, mapValue : Text }
+              , content : List XML
+              , name : Text
+              } →
+                XML
+          }
+        ) →
+        xml.text d
+
+in  text

package.dhall

@@ -17,4 +17,5 @@
   , Path = ./Path/package.dhall nix
   , Set = ./Set/package.dhall nix
   , Text = ./Text/package.dhall nix
+  , XML = ./XML/package.dhall
   }