feat(doc): Make all types link to their definition

Closes #552

base/src/types/mod.rs

@@ -1275,7 +1275,7 @@ impl<Id> ArcType<Id> {
         top(self).pretty(&Printer::new(arena, &()))
     }
 
-    pub fn display(&self, width: usize) -> TypeFormatter<Id, Self> {
+    pub fn display<A>(&self, width: usize) -> TypeFormatter<Id, Self, A> {
         TypeFormatter::new(self).width(width)
     }
 }
@@ -1907,8 +1907,8 @@ where
             // This should not be displayed normally as it should only exist in `ExtendRow`
             // which handles `EmptyRow` explicitly
             Type::EmptyRow => arena.text("EmptyRow"),
-            Type::Ident(ref id) => arena.text(id.as_ref()),
-            Type::Alias(ref alias) => arena.text(alias.name.as_ref()),
+            Type::Ident(ref id) => printer.symbol(id),
+            Type::Alias(ref alias) => printer.symbol(&alias.name),
         };
         match **typ {
             Type::App(..) | Type::ExtendRow { .. } | Type::Variant(..) | Type::Function(..) => doc,

base/src/types/pretty_print.rs

@@ -76,29 +76,32 @@ impl From<bool> for Filter {
     }
 }
 
-pub struct TypeFormatter<'a, I, T>
+pub struct TypeFormatter<'a, I, T, A>
 where
     I: 'a,
     T: 'a,
+    A: 'a,
 {
     width: usize,
     typ: &'a T,
     filter: &'a Fn(&I) -> Filter,
+    annotate_symbol: &'a Fn(&I) -> Option<A>,
     _marker: PhantomData<I>,
 }
 
-impl<'a, I, T> TypeFormatter<'a, I, T> {
+impl<'a, I, T, A> TypeFormatter<'a, I, T, A> {
     pub fn new(typ: &'a T) -> Self {
         TypeFormatter {
             width: 80,
             typ: typ,
             filter: &|_| Filter::Retain,
+            annotate_symbol: &|_| None,
             _marker: PhantomData,
         }
     }
 }
 
-impl<'a, I, T> TypeFormatter<'a, I, T> {
+impl<'a, I, T, A> TypeFormatter<'a, I, T, A> {
     pub fn width(mut self, width: usize) -> Self {
         self.width = width;
         self
@@ -109,7 +112,12 @@ impl<'a, I, T> TypeFormatter<'a, I, T> {
         self
     }
 
-    pub fn pretty<A>(&self, arena: &'a Arena<'a, A>) -> DocBuilder<'a, Arena<'a, A>, A>
+    pub fn annotate_symbol(mut self, annotate_symbol: &'a Fn(&I) -> Option<A>) -> Self {
+        self.annotate_symbol = annotate_symbol;
+        self
+    }
+
+    pub fn pretty(&self, arena: &'a Arena<'a, A>) -> DocBuilder<'a, Arena<'a, A>, A>
     where
         T: Deref<Target = Type<I, T>> + HasSpan + Commented + 'a,
         I: AsRef<str>,
@@ -120,19 +128,21 @@ impl<'a, I, T> TypeFormatter<'a, I, T> {
             arena,
             source: &(),
             filter: self.filter,
+            annotate_symbol: self.annotate_symbol,
         })
     }
 
-    pub fn build<A>(&self, arena: &'a Arena<'a, A>, source: &'a Source) -> Printer<'a, I, A> {
+    pub fn build(&self, arena: &'a Arena<'a, A>, source: &'a Source) -> Printer<'a, I, A> {
         Printer {
             arena,
             source,
             filter: self.filter,
+            annotate_symbol: self.annotate_symbol,
         }
     }
 }
 
-impl<'a, I, T> fmt::Display for TypeFormatter<'a, I, T>
+impl<'a, I, T> fmt::Display for TypeFormatter<'a, I, T, ()>
 where
     T: Deref<Target = Type<I, T>> + HasSpan + Commented + 'a,
     I: AsRef<str>,
@@ -156,6 +166,7 @@ pub struct Printer<'a, I: 'a, A: 'a> {
     pub arena: &'a Arena<'a, A>,
     pub source: &'a Source,
     filter: &'a Fn(&I) -> Filter,
+    annotate_symbol: &'a Fn(&I) -> Option<A>,
 }
 
 impl<'a, I, A> Printer<'a, I, A> {
@@ -164,13 +175,25 @@ impl<'a, I, A> Printer<'a, I, A> {
             arena,
             source,
             filter: &|_| Filter::Retain,
+            annotate_symbol: &|_| None,
         }
     }
 
     pub fn filter(&self, field: &I) -> Filter {
         (self.filter)(field)
     }
 
+    pub fn symbol(&self, symbol: &'a I) -> DocBuilder<'a, Arena<'a, A>, A>
+    where
+        I: AsRef<str>,
+    {
+        let doc = self.arena.text(symbol.as_ref());
+        match (self.annotate_symbol)(symbol) {
+            Some(ann) => doc.annotate(ann),
+            None => doc,
+        }
+    }
+
     pub fn space_before(&self, pos: BytePos) -> DocBuilder<'a, Arena<'a, A>, A> {
         let (doc, comments) = self.comments_before_(pos);
         if let Doc::Nil = doc.1 {

base/tests/types.rs

@@ -315,7 +315,7 @@ fn break_record() {
             ),
         ],
     );
-    let arena = Arena::new();
+    let arena = Arena::<()>::new();
     let source = &();
     let printer = pretty_print::Printer::new(&arena, source);
     let typ = arena

doc/src/doc/index.html

@@ -24,7 +24,7 @@ <h2>Modules</h2>
         {{#each modules}}
             <tr>
                 <td>
-                    <a href="{{symbol_link name}}">{{name}}</a>
+                    <a href="{{module_link name}}">{{name}}</a>
                 </td>
                 <td valign="middle">
                     {{markdown_first_paragraph comment}}

doc/src/doc/module.html

@@ -20,7 +20,7 @@
             <ul class="nav flex-column">
                 {{#each sibling_modules}}
                 <li class="nav-item">
-                    <a class="nav-link active" href="{{symbol_link this}}">{{this}}</a>
+                    <a class="nav-link active" href="{{module_link this}}">{{this}}</a>
                 </li> 
                 {{/each}}
             </ul>
@@ -36,7 +36,7 @@ <h2 class="pb-3 mb-4 border-bottom"><a class="anchor field" id="Types" href="#Ty
             {{#each record.types}}
 
                 <h4>
-                    <pre>type <a class="anchor field" id="type.{{name}}" href="#type.{{name}}">{{name}}</a>{{#each args}} {{name}}{{/each}} = {{type~}}
+                    <pre>type <a class="anchor field" id="type.{{name}}" href="#type.{{name}}">{{name}}</a>{{#each args}} {{name}}{{/each}} = {{{type~}}}
                     </pre>
                 </h4>
                 <div class="docblock">{{markdown comment}}</div>
@@ -52,7 +52,7 @@ <h4>
                 <pre>let <a class="anchor field" id="value.{{name}}" href="#value.{{name}}">{{name}}</a>
                     {{~#each args~}}
                         {{~#if implicit}} ?{{name}}{{else}} {{name}}{{~/if~}}
-                    {{~/each}} : {{type~}}
+                    {{~/each}} : {{{type~}}}
                 </pre>
                 </h4>
                 <div class="docblock">{{markdown comment}}</div>