diff options
Diffstat (limited to 'demo/prose')
| -rw-r--r-- | demo/prose | 8 |
1 files changed, 6 insertions, 2 deletions
@@ -44,12 +44,16 @@ rec.urp <p>Crafting webs of interlinked pages is easy, using recursion.</p> +counter.urp + +<p>It is also easy to pass state around via functions, in the style commonly associated with "continuation-based" web servers. As is usual for such systems, all state is stored on the client side. In this case, it is encoded in URLs.</p> + +<p>In the implementation of <tt>Counter.counter</tt>, we see the notation <tt>{[...]}</tt>, which uses type classes to inject values of different types (<tt>int</tt> in this case) into XML. It's probably worth stating explicitly that XML fragments <i>are not strings</i>, so that the type-checker will enforce that our final piece of XML is valid.</p> + form.urp <p>Here we see a basic form. The type system tracks which form inputs we include, and it enforces that the form handler function expects a record containing exactly those fields, with exactly the proper types.</p> -<p>In the implementation of <tt>handler</tt>, we see the notation <tt>{[...]}</tt>, which uses type classes to inject values of different types (<tt>string</tt> and <tt>bool</tt> in this case) into XML. It's probably worth stating explicitly that XML fragments <i>are not strings</i>, so that the type-checker will enforce that our final piece of XML is valid.</p> - listShop.urp <p>This example shows off algebraic datatypes, parametric polymorphism, and functors.</p> |