summaryrefslogtreecommitdiff
path: root/demo/prose
diff options
context:
space:
mode:
authorGravatar Adam Chlipala <adamc@hcoop.net>2009-03-10 11:18:01 -0400
committerGravatar Adam Chlipala <adamc@hcoop.net>2009-03-10 11:18:01 -0400
commita8f3cc9e254122906318531ef39b5cae89829ef4 (patch)
tree99e4bdad36025df9b3bd37c782f9dd36f052307a /demo/prose
parent5646b9630eb86f0d4f393dce6b7fc76cea87421f (diff)
React demo
Diffstat (limited to 'demo/prose')
-rw-r--r--demo/prose6
1 files changed, 6 insertions, 0 deletions
diff --git a/demo/prose b/demo/prose
index ab32a753..9c2639ff 100644
--- a/demo/prose
+++ b/demo/prose
@@ -191,3 +191,9 @@ alert.urp
<p>Ur/Web makes it easy to write code whose execution should be distributed between the web server and client web browsers. Server-side code is compiled to efficient native code, and client-side code is compiled to JavaScript. Ur/Web programmers don't need to worry about these details, because the language and standard library provide a uniform ML-like interface for the whole process.</p>
<p>Here's an example of a button that, when clicked, opens an alert dialog on the client.</p>
+
+react.urp
+
+<p>Most client-side JavaScript programs modify page contents imperatively, but Ur/Web is based on functional-reactive programming instead. Programs allocate data sources and then describe the page as a pure function of those data sources. When the sources change, the page changes automatically.</p>
+
+<p>Here's an example where a button modifies a data source that affects some text on the page. The affected portion of the page is indicated with the pseudo-HTML tag <tt>dyn</tt>, whose <tt>signal</tt> attribute specifies one of these pure functions over mutable sources. A source containing data of type <tt>t</tt> has type <tt>source t</tt> and is created with the <tt>source</tt> operation within the <tt>transaction</tt> monad. Functions over sources are represented in the monad <tt>signal</tt>. Like in Haskell, we overload monad notations, so that the same return and bind operators can be used to write signals and transactions. The <tt>signal</tt> function coerces a source to a signal.</p>