Ur/Web: lib/js/urweb.js comparison

comparison lib/js/urweb.js @ 1260:25ebd8c4fafb

Thunking recursive JavaScripted function ASTs, to reduce page load time dramatically

author	Adam Chlipala <adamc@hcoop.net>
date	Sat, 22 May 2010 14:09:06 -0400
parents	83b1853d1e58
children	003df929ee08

comparison

equal deleted inserted replaced

-:83b1853d1e58
+:25ebd8c4fafb
 // Detect browser quirks that we should be aware of.
 function needsDynPrefix() {
 var span = document.createElement("span");
 span.innerHTML = "<script>alert('test');</script>";
 var scripts = span.getElementsByTagName("script");
 return scripts.length == 0;
 }
 var dynPrefix = needsDynPrefix() ? "<span style=\"display:none\">A</span>" : "";
 // Function versions of operators
 // Lists
 function cons(v, ls) {
 return { next : ls, data : v };
 }
 function rev(ls) {
 var acc = null;
 for (; ls; ls = ls.next)
 acc = cons(ls.data, acc);
 return acc;
 }
 function concat(ls1, ls2) {
 var acc = ls2;
 ls1 = rev(ls1);
 for (; ls1; ls1 = ls1.next)
 acc = cons(ls1.data, acc);
 return acc;
 }
 function member(x, ls) {
 for (; ls; ls = ls.next)
 if (ls.data == x)
 return true;
 return false;
 }
 function remove(x, ls) {
 var acc = null;
 for (; ls; ls = ls.next)
 if (ls.data == x)
 return concat(acc, ls.next);
+else
+acc = cons(ls.data, acc);
+return ls;
+}
+function union(ls1, ls2) {
+var acc = ls2;
+for (; ls1; ls1 = ls1.next)
+if (!member(ls1.data, ls2))
+acc = cons(ls1.data, acc);
+return acc;
+}
+function length(ls) {
+var acc = 0;
+for (; ls; ls = ls.next)
+++acc;
+return acc;
+}
+// Error handling
+function whine(msg) {
+alert(msg);
+throw msg;
+}
+function pf(loc) {
+throw ("Pattern match failure (" + loc + ")");
+}
+function runHandlers(kind, ls, arg) {
+if (ls == null)
+alert(kind + ": " + arg);
+for (; ls; ls = ls.next)
+try {
+exec({c:"a", f:{c:"a", f:ls.data, x:{c:"c", v:arg}}, x:{c:"c", v:null}});
+} catch (v) { }
+}
+var errorHandlers = null;
+function onError(f) {
+errorHandlers = cons(f, errorHandlers);
+}
+function er(s) {
+runHandlers("Error", errorHandlers, s);
+throw {uw_error: s};
+}
+var failHandlers = null;
+function onFail(f) {
+failHandlers = cons(f, failHandlers);
+}
+function doExn(v) {
+if (v == null || v.uw_error == null) {
+var s = (v == null ? "null" : v.message ? v.message : v.toString());
+if (v != null && v.fileName && v.lineNumber)
+s += " (" + v.fileName + ":" + v.lineNumber + ")";
+runHandlers("Fail", failHandlers, s);
+}
+}
+var disconnectHandlers = null;
+function flift(f) {
+return {env:cons(f,null), body:{c:"v", n:1}};
+}
+function onDisconnect(f) {
+disconnectHandlers = cons(flift(f), disconnectHandlers);
+}
+function discon() {
+runHandlers("Disconnect", disconnectHandlers, null);
+}
+var connectHandlers = null;
+function onConnectFail(f) {
+connectHandlers = cons(flift(f), connectHandlers);
+}
+function conn() {
+runHandlers("Connect", connectHandlers, null);
+}
+var serverHandlers = null;
+function onServerError(f) {
+serverHandlers = cons(f, serverHandlers);
+}
+function servErr(s) {
+window.setTimeout(function () { runHandlers("Server", serverHandlers, s); }, 0);
+}
+// Embedding closures in XML strings
+function cs(f) {
+return {closure: f};
+}
+function isWeird(v) {
+return v.closure != null || v.cat1 != null;
+}
+function cat(s1, s2) {
+if (isWeird(s1) || isWeird(s2))
+return {cat1: s1, cat2: s2};
 else
-acc = cons(ls.data, acc);
+return s1 + s2;
-return ls;
-}
-function union(ls1, ls2) {
-var acc = ls2;
-for (; ls1; ls1 = ls1.next)
-if (!member(ls1.data, ls2))
-acc = cons(ls1.data, acc);
-return acc;
-}
-function length(ls) {
-var acc = 0;
-for (; ls; ls = ls.next)
-++acc;
-return acc;
-}
-// Error handling
-function whine(msg) {
-alert(msg);
-throw msg;
-}
-function pf(loc) {
-throw ("Pattern match failure (" + loc + ")");
-}
-function runHandlers(kind, ls, arg) {
-if (ls == null)
-alert(kind + ": " + arg);
-for (; ls; ls = ls.next)
-try {
-exec({c:"a", f:{c:"a", f:ls.data, x:{c:"c", v:arg}}, x:{c:"c", v:null}});
-} catch (v) { }
-}
-var errorHandlers = null;
-function onError(f) {
-errorHandlers = cons(f, errorHandlers);
-}
-function er(s) {
-runHandlers("Error", errorHandlers, s);
-throw {uw_error: s};
-}
-var failHandlers = null;
-function onFail(f) {
-failHandlers = cons(f, failHandlers);
-}
-function doExn(v) {
-if (v == null || v.uw_error == null) {
-var s = (v == null ? "null" : v.message ? v.message : v.toString());
-if (v != null && v.fileName && v.lineNumber)
-s += " (" + v.fileName + ":" + v.lineNumber + ")";
-runHandlers("Fail", failHandlers, s);
-}
-}
-var disconnectHandlers = null;
-function flift(f) {
-return {env:cons(f,null), body:{c:"v", n:1}};
-}
-function onDisconnect(f) {
-disconnectHandlers = cons(flift(f), disconnectHandlers);
-}
-function discon() {
-runHandlers("Disconnect", disconnectHandlers, null);
-}
-var connectHandlers = null;
-function onConnectFail(f) {
-connectHandlers = cons(flift(f), connectHandlers);
-}
-function conn() {
-runHandlers("Connect", connectHandlers, null);
-}
-var serverHandlers = null;
-function onServerError(f) {
-serverHandlers = cons(f, serverHandlers);
-}
-function servErr(s) {
-window.setTimeout(function () { runHandlers("Server", serverHandlers, s); }, 0);
-}
-// Embedding closures in XML strings
-function cs(f) {
-return {closure: f};
-}
-function isWeird(v) {
-return v.closure != null || v.cat1 != null;
-}
-function cat(s1, s2) {
-if (isWeird(s1) || isWeird(s2))
-return {cat1: s1, cat2: s2};
-else
-return s1 + s2;
 }
 var closures = [];
 var freeClosures = null;
 function newClosure(f) {
 var n;
 if (freeClosures == null) {
 n = closures.length;
 } else {
 n = freeClosures.data;
 freeClosures = freeClosures.next;
 }
 closures[n] = f;
 return n;
 }
 function freeClosure(n) {
 closures[n] = null;
 freeClosures = cons(n, freeClosures);
 }
 function cr(n) {
 return closures[n];
 }
 function flatten(cls, tr) {
 if (tr.cat1 != null)
 return flatten(cls, tr.cat1) + flatten(cls, tr.cat2);
 else if (tr.closure != null) {
 var cl = newClosure(tr.closure);
 cls.v = cons(cl, cls.v);
 return "cr(" + cl + ")";
 } else
 return tr;
 }
 function flattenLocal(s) {
 var cls = {v : null};
 var r = flatten(cls, s);
 for (cl = cls.v; cl != null; cl = cl.next)
 freeClosure(cl.data);
 return r;
 }
 // Dynamic tree management
 function populate(node) {
 var s = node.signal;
 var oldSources = node.sources;
 try {
 var sr = execF(s, null);
 var newSources = sr._sources;
 for (var sp = oldSources; sp; sp = sp.next)
 if (!member(sp.data, newSources))
 sp.data.dyns = remove(node, sp.data.dyns);
 for (var sp = newSources; sp; sp = sp.next)
 if (!member(sp.data, oldSources))
 sp.data.dyns = cons(node, sp.data.dyns);
 node.sources = newSources;
 node.recreate(sr._data);
 } catch (v) {
 doExn(v);
 }
 }
 function sc(v) {
 return {data : v, dyns : null};
 }
 function sv(s, v) {
 s.data = v;
 for (var ls = s.dyns; ls; ls = ls.next)
 if (!ls.dead)
 populate(ls.data);
 }
 function sg(s) {
 return s.data;
 }
 function ss(s) {
 return {env:cons(s, null), body:{c:"r", l:
 cons({n:"sources", v:{c:"c", v:cons(s, null)}},
 cons({n:"data", v:{c:"f", f:sg, a:cons({c:"v", n:1}, null)}}, null))}};
 }
 function sr(v) {
 return {env:null, body:{c:"c", v:{_sources : null, _data : v}}};
 }
 function sb(x,y) {
 return {env:cons(y,cons(x,null)),
 body:{c:"=",
 e1:{c:"a", f:{c:"v", n:2}, x:{c:"c", v:null}},
 e2:{c:"=",
 e1:{c:"a",
 f:{c:"a", f:{c:"v", n:2}, x:{c:".", r:{c:"v", n:0}, f:"data"}},
 x:{c:"c", v:null}},
 e2:{c:"r", l:cons(
 {n:"sources", v:{c:"f", f:union, a:cons({c:".", r:{c:"v", n:1}, f:"sources"},
 cons({c:".", r:{c:"v", n:0}, f:"sources"}, null))}},
 cons({n:"data", v:{c:".", r:{c:"v", n:0}, f:"data"}}, null))}}}};
 }
 function scur(s) {
 return execF(s, null)._data;
 }
 function lastParent() {
 var pos = document.body;
 while (pos.lastChild && pos.lastChild.nodeType == 1)
 pos = pos.lastChild;
 pos = pos.parentNode;
 return pos;
 }
 function parent() {
 return thisScript ? thisScript.parentNode : lastParent();
 }
 function addNode(node) {
 if (thisScript)
 thisScript.parentNode.replaceChild(node, thisScript);
 else
 lastParent().appendChild(node);
 }
 var thisScript = null;
 function runScripts(node) {
 if (node.getElementsByTagName) {
 var savedScript = thisScript;
 var scripts = node.getElementsByTagName("script"), scriptsCopy = [];
 var len = scripts.length;
 for (var i = 0; i < len; ++i)
 scriptsCopy[i] = scripts[i];
 for (var i = 0; i < len; ++i) {
 thisScript = scriptsCopy[i];
 try {
 eval(thisScript.text);
 } catch (v) {
 doExn(v);
 }
 if (thisScript.parentNode)
 thisScript.parentNode.removeChild(thisScript);
 }
 thisScript = savedScript;
 }
 }
 // Dynamic tree entry points
 function killScript(scr) {
 scr.dead = true;
 for (var ls = scr.sources; ls; ls = ls.next)
 ls.data.dyns = remove(scr, ls.data.dyns);
 for (var ls = scr.closures; ls; ls = ls.next)
 freeClosure(ls.data);
 }
 function dyn(pnode, s) {
 var x = document.createElement("script");
 x.dead = false;
 x.signal = s;
 x.sources = null;
 x.closures = null;
 var firstChild = null;
 x.recreate = function(v) {
 for (var ls = x.closures; ls; ls = ls.next)
 freeClosure(ls.data);
-var next;
-for (var child = firstChild; child && child != x; child = next) {
-next = child.nextSibling;
-killScript(child);
-if (child.getElementsByTagName) {
-var arr = child.getElementsByTagName("script");
-for (var i = 0; i < arr.length; ++i)
-killScript(arr[i]);
-}
-if (child.parentNode)
-child.parentNode.removeChild(child);
-}
-var cls = {v : null};
-var html = flatten(cls, v);
-if (pnode != "table" && pnode != "tr")
-html = dynPrefix + html;
-x.closures = cls.v;
-if (pnode == "table") {
-var dummy = document.createElement("body");
-dummy.innerHTML = "<table>" + html + "</table>";
-runScripts(dummy);
-var table = x.parentNode;
-if (table) {
-firstChild = null;
-var tbody;
-var arr = dummy.getElementsByTagName("tbody");
-var tbody;
-if (arr.length > 0 && arr[0].parentNode == dummy.firstChild) {
-tbody = arr[0];
-var next;
-for (var node = dummy.firstChild.firstChild; node; node = next) {
-next = node.nextSibling;
-if (node.tagName != "TBODY")
-tbody.appendChild(node);
-}
-} else
-tbody = dummy.firstChild;
 var next;
-firstChild = document.createElement("script");
+for (var child = firstChild; child && child != x; child = next) {
-table.insertBefore(firstChild, x);
+next = child.nextSibling;
-for (var node = tbody.firstChild; node; node = next) {
-next = node.nextSibling;
+killScript(child);
-table.insertBefore(node, x);
+if (child.getElementsByTagName) {
+var arr = child.getElementsByTagName("script");
+for (var i = 0; i < arr.length; ++i)
+killScript(arr[i]);
+}
+if (child.parentNode)
+child.parentNode.removeChild(child);
 }
-}
-} else if (pnode == "tr") {
+var cls = {v : null};
-var dummy = document.createElement("body");
+var html = flatten(cls, v);
-dummy.innerHTML = "<table><tr>" + html + "</tr></table>";
+if (pnode != "table" && pnode != "tr")
-runScripts(dummy);
+html = dynPrefix + html;
-var table = x.parentNode;
+x.closures = cls.v;
-if (table) {
+if (pnode == "table") {
-var arr = dummy.getElementsByTagName("tr");
+var dummy = document.createElement("body");
-firstChild = null;
+dummy.innerHTML = "<table>" + html + "</table>";
-var tr;
+runScripts(dummy);
-if (arr.length > 0 && table != null)
+var table = x.parentNode;
-tr = arr[0];
-else
+if (table) {
-tr = dummy.firstChild;
+firstChild = null;
+var tbody;
-var next;
-firstChild = document.createElement("script");
+var arr = dummy.getElementsByTagName("tbody");
-table.insertBefore(firstChild, x);
-for (var node = tr.firstChild; node; node = next) {
+var tbody;
-next = node.nextSibling;
+if (arr.length > 0 && arr[0].parentNode == dummy.firstChild) {
-table.insertBefore(node, x);
+tbody = arr[0];
+var next;
+for (var node = dummy.firstChild.firstChild; node; node = next) {
+next = node.nextSibling;
+if (node.tagName != "TBODY")
+tbody.appendChild(node);
+}
+} else
+tbody = dummy.firstChild;
+var next;
+firstChild = document.createElement("script");
+table.insertBefore(firstChild, x);
+for (var node = tbody.firstChild; node; node = next) {
+next = node.nextSibling;
+table.insertBefore(node, x);
+}
+}
+} else if (pnode == "tr") {
+var dummy = document.createElement("body");
+dummy.innerHTML = "<table><tr>" + html + "</tr></table>";
+runScripts(dummy);
+var table = x.parentNode;
+if (table) {
+var arr = dummy.getElementsByTagName("tr");
+firstChild = null;
+var tr;
+if (arr.length > 0 && table != null)
+tr = arr[0];
+else
+tr = dummy.firstChild;
+var next;
+firstChild = document.createElement("script");
+table.insertBefore(firstChild, x);
+for (var node = tr.firstChild; node; node = next) {
+next = node.nextSibling;
+table.insertBefore(node, x);
+}
+}
+} else {
+firstChild = document.createElement("span");
+firstChild.innerHTML = html;
+runScripts(firstChild);
+if (x.parentNode)
+x.parentNode.insertBefore(firstChild, x);
 }
-}
+};
-} else {
-firstChild = document.createElement("span");
+addNode(x);
-firstChild.innerHTML = html;
+populate(x);
-runScripts(firstChild);
-if (x.parentNode)
-x.parentNode.insertBefore(firstChild, x);
-}
-};
-addNode(x);
-populate(x);
 }
 function input(x, s, recreate, type) {
 if (type) x.type = type;
 x.dead = false;
 x.signal = ss(s);
 x.sources = null;
 x.recreate = recreate(x);
 addNode(x);
 populate(x);
 return x;
 }
 function inp(s) {
 var x = input(document.createElement("input"), s,
 function(x) { return function(v) { if (x.value != v) x.value = v; }; });
 x.value = s.data;
 x.onkeyup = function() { sv(s, x.value) };
 return x;
 }
 function sel(s, content) {
 var dummy = document.createElement("span");
 dummy.innerHTML = "<select>" + content + "</select>";
 var x = input(dummy.firstChild, s, function(x) { return function(v) { if (x.value != v) x.value = v; }; });
 x.value = s.data;
 if (x.value != s.data)
 sv(s, x.value);
 x.onchange = function() { sv(s, x.value) };
 return x;
 }
 function chk(s) {
 var x = input(document.createElement("input"), s,
 function(x) { return function(v) { if (x.checked != v) x.checked = v; }; }, "checkbox");
 x.defaultChecked = x.checked = s.data;
 x.onclick = function() { sv(s, x.checked) };
 return x;
 }
 function tbx(s) {
 var x = input(document.createElement("textarea"), s,
 function(x) { return function(v) { if (x.innerHTML != v) x.innerHTML = v; }; });
 x.innerHTML = s.data;
 x.onkeyup = function() { sv(s, x.value) };
 return x;
 }
 function addOnChange(x, f) {
 var old = x.onchange;
 x.onchange = function() { old(); f (); };
 }
 // Basic string operations
 function eh(x) {
 if (x == null)
 return "NULL";
 else
 return x.split("&").join("&amp;").split("<").join("&lt;").split(">").join("&gt;");
 }
 function ts(x) { return x.toString() }
 function bs(b) { return (b ? "True" : "False") }
 function id(x) { return x; }
 function sub(s, i) { return s.charAt(i); }
 function suf(s, i) { return s.substring(i); }
 function slen(s) { return s.length; }
 function sidx(s, ch) {
 var r = s.indexOf(ch);
 if (r == -1)
+return null;
+else
+return r;
+}
+function sspn(s, chs) {
+for (var i = 0; i < s.length; ++i)
+if (chs.indexOf(s.charAt(i)) != -1)
+return i;
 return null;
-else
-return r;
-}
-function sspn(s, chs) {
-for (var i = 0; i < s.length; ++i)
-if (chs.indexOf(s.charAt(i)) != -1)
-return i;
-return null;
 }
 function schr(s, ch) {
 var r = s.indexOf(ch);
 if (r == -1)
 return null;
 else
 return s.substring(r);
 }
 function ssub(s, start, len) {
 return s.substring(start, start+len);
 }
 function pi(s) {
 var r = parseInt(s);
 if (r.toString() == s)
 return r;
 else
 er("Can't parse int: " + s);
 }
 function pfl(s) {
 var r = parseFloat(s);
 if (r.toString() == s)
 return r;
 else
 er("Can't parse float: " + s);
 }
 function pio(s) {
 var r = parseInt(s);
 if (r.toString() == s)
 return r;
 else
 return null;
 }
 function pflo(s) {
 var r = parseFloat(s);
 if (r.toString() == s)
 return r;
 else
 return null;
 }
 function uf(s) {
 if (s.length == 0)
 return "_";
 s = s.replace(new RegExp ("\\.", "g"), ".2E");
 return (s.charAt(0) == '_' ? "_" : "") + encodeURIComponent(s).replace(new RegExp ("%", "g"), ".");
 }
 function uu(s) {
 if (s.length > 0 && s.charAt(0) == '_') {
 s = s.substring(1);
 } else if (s.length >= 3 && (s.charAt(0) == '%' || s.charAt(0) == '.')
 && s.charAt(1) == '5' && (s.charAt(2) == 'f' || s.charAt(2) == 'F'))
 s = s.substring(3);
 s = s.replace(new RegExp ("\\+", "g"), " ");
 s = s.replace(new RegExp ("\\.", "g"), "%");
 return decodeURIComponent(s);
 }
 function atr(s) {
 return s.replace(new RegExp ("\"", "g"), "&quot;").replace(new RegExp ("&", "g"), "&amp;")
 }
 function ub(b) {
 return b ? "1" : "0";
 }
 function uul(getToken, getData) {
 var tok = getToken();
 if (tok == "Nil") {
 return null;
 } else if (tok == "Cons") {
 var d = getData();
 var l = uul(getToken, getData);
 return {_1:d, _2:l};
 } else
 whine("Can't unmarshal list (" + tok + ")");
 }
 function strcmp(str1, str2) {
 return ((str1 == str2) ? 0 : ((str1 > str2) ? 1 : -1));
 }
 // Remote calls
 var url_prefix = "/";
 var timeout = 60;
 function getXHR(uri)
 {
-try {
-return new XMLHttpRequest();
-} catch (e) {
 try {
-return new ActiveXObject("Msxml2.XMLHTTP");
+return new XMLHttpRequest();
 } catch (e) {
 try {
-return new ActiveXObject("Microsoft.XMLHTTP");
+return new ActiveXObject("Msxml2.XMLHTTP");
 } catch (e) {
-whine("Your browser doesn't seem to support AJAX.");
+try {
-}
+return new ActiveXObject("Microsoft.XMLHTTP");
-}
+} catch (e) {
-}
+whine("Your browser doesn't seem to support AJAX.");
+}
+}
+}
 }
 var sig = null;
 var unloading = false, inFlight = null;
 function unload() {
 unloading = true;
 for (; inFlight; inFlight = inFlight.next) {
 inFlight.data.abort();
 }
 }
 function requestUri(xhr, uri, needsSig) {
 if (unloading)
 return;
 xhr.open("POST", uri, true);
 xhr.setRequestHeader("Content-type", "text/plain");
 xhr.setRequestHeader("Content-length", "0");
 xhr.setRequestHeader("Connection", "close");
 if (client_id != null) {
 xhr.setRequestHeader("UrWeb-Client", client_id.toString());
 xhr.setRequestHeader("UrWeb-Pass", client_pass.toString());
 }
 if (needsSig) {
 if (sig == null)
 whine("Missing cookie signature!");
 xhr.setRequestHeader("UrWeb-Sig", sig);
 }
 inFlight = cons(xhr, inFlight);
 xhr.send(null);
 }
 function xhrFinished(xhr) {
 xhr.abort();
 inFlight = remove(xhr, inFlight);
 }
 function unurlify(parse, s) {
 return parse(s);
 }
 function rc(prefix, uri, parse, k, needsSig) {
 uri = cat(prefix, uri);
 uri = flattenLocal(uri);
 var xhr = getXHR();
 xhr.onreadystatechange = function() {
 if (xhr.readyState == 4) {
 var isok = false;
 try {
 if (xhr.status == 200)
 isok = true;
 } catch (e) { }
 if (isok) {
+try {
+k(parse(xhr.responseText));
+} catch (v) {
+doExn(v);
+}
+} else {
+conn();
+}
+xhrFinished(xhr);
+}
+};
+requestUri(xhr, uri, needsSig);
+}
+function path_join(s1, s2) {
+if (s1.length > 0 && s1.charAt(s1.length-1) == '/')
+return s1 + s2;
+else
+return s1 + "/" + s2;
+}
+var channels = [];
+function newQueue() {
+return { front : null, back : null };
+}
+function enqueue(q, v) {
+if (q.front == null) {
+q.front = cons(v, null);
+q.back = q.front;
+} else {
+var node = cons(v, null);
+q.back.next = node;
+q.back = node;
+}
+}
+function dequeue(q) {
+if (q.front == null)
+return null;
+else {
+var r = q.front.data;
+q.front = q.front.next;
+if (q.front == null)
+q.back = null;
+return r;
+}
+}
+function newChannel() {
+return { msgs : newQueue(), listeners : newQueue() };
+}
+function listener() {
+var uri = path_join(url_prefix, ".msgs");
+var xhr = getXHR();
+var tid, orsc, onTimeout;
+var connect = function () {
+xhr.onreadystatechange = orsc;
+tid = window.setTimeout(onTimeout, timeout * 500);
+requestUri(xhr, uri, false);
+}
+orsc = function() {
+if (xhr.readyState == 4) {
+window.clearTimeout(tid);
+var isok = false;
+try {
+if (xhr.status == 200)
+isok = true;
+} catch (e) { }
+if (isok) {
+var text = xhr.responseText
+if (text == "")
+return;
+var lines = text.split("\n");
+if (lines.length < 2) {
+discon();
+return;
+}
+for (var i = 0; i+1 < lines.length; i += 2) {
+var chn = lines[i];
+var msg = lines[i+1];
+if (chn < 0)
+whine("Out-of-bounds channel in message from remote server");
+var ch;
+if (chn >= channels.length || channels[chn] == null) {
+ch = newChannel();
+channels[chn] = ch;
+} else
+ch = channels[chn];
+var listener = dequeue(ch.listeners);
+if (listener == null) {
+enqueue(ch.msgs, msg);
+} else {
+try {
+listener(msg);
+} catch (v) {
+doExn(v);
+}
+}
+}
+xhrFinished(xhr);
+connect();
+}
+else {
+try {
+if (xhr.status != 0)
+servErr("Error querying remote server for messages: " + xhr.status);
+} catch (e) { }
+}
+}
+};
+onTimeout = function() {
+xhrFinished(xhr);
+connect();
+};
+connect();
+}
+function rv(chn, parse, k) {
+if (chn == null)
+return;
+if (chn < 0)
+whine("Out-of-bounds channel receive");
+var ch;
+if (chn >= channels.length || channels[chn] == null) {
+ch = newChannel();
+channels[chn] = ch;
+} else
+ch = channels[chn];
+var msg = dequeue(ch.msgs);
+if (msg == null) {
+enqueue(ch.listeners, function(msg) { k(parse(msg)); });
+} else {
 try {
-k(parse(xhr.responseText));
+k(parse(msg));
 } catch (v) {
 doExn(v);
 }
-} else {
+}
-conn();
+}
-}
+function sl(ms, k) {
-xhrFinished(xhr);
+window.setTimeout(function() { k(null); }, ms);
 }
-};
+function sp(e) {
-requestUri(xhr, uri, needsSig);
+execF(e, null);
 }
-function path_join(s1, s2) {
-if (s1.length > 0 && s1.charAt(s1.length-1) == '/')
+// Key events
-return s1 + s2;
-else
+var uw_event = null;
-return s1 + "/" + s2;
-}
+function kc() {
+return window.event ? uw_event.keyCode : uw_event.which;
-var channels = [];
+}
-function newQueue() {
-return { front : null, back : null };
+// The Ur interpreter
-}
-function enqueue(q, v) {
+var urfuncs = [];
-if (q.front == null) {
-q.front = cons(v, null);
+function lookup(env, n) {
-q.back = q.front;
+while (env != null) {
-} else {
+if (n == 0)
-var node = cons(v, null);
+return env.data;
-q.back.next = node;
+else {
-q.back = node;
+--n;
-}
+env = env.next;
-}
-function dequeue(q) {
-if (q.front == null)
-return null;
-else {
-var r = q.front.data;
-q.front = q.front.next;
-if (q.front == null)
-q.back = null;
-return r;
-}
-}
-function newChannel() {
-return { msgs : newQueue(), listeners : newQueue() };
-}
-function listener() {
-var uri = path_join(url_prefix, ".msgs");
-var xhr = getXHR();
-var tid, orsc, onTimeout;
-var connect = function () {
-xhr.onreadystatechange = orsc;
-tid = window.setTimeout(onTimeout, timeout * 500);
-requestUri(xhr, uri, false);
-}
-orsc = function() {
-if (xhr.readyState == 4) {
-window.clearTimeout(tid);
-var isok = false;
-try {
-if (xhr.status == 200)
-isok = true;
-} catch (e) { }
-if (isok) {
-var text = xhr.responseText
-if (text == "")
-return;
-var lines = text.split("\n");
-if (lines.length < 2) {
-discon();
-return;
 }
+}
-for (var i = 0; i+1 < lines.length; i += 2) {
-var chn = lines[i];
+whine("Out-of-bounds Ur variable reference");
-var msg = lines[i+1];
+}
-if (chn < 0)
+function execP(env, p, v) {
-whine("Out-of-bounds channel in message from remote server");
+switch (p.c) {
+case "w":
-var ch;
+return env;
+case "v":
-if (chn >= channels.length || channels[chn] == null) {
+return cons(v, env);
-ch = newChannel();
+case "c":
-channels[chn] = ch;
+if (v == p.v)
-} else
+return env;
-ch = channels[chn];
+else
+return false;
-var listener = dequeue(ch.listeners);
+case "s":
-if (listener == null) {
+if (v == null)
-enqueue(ch.msgs, msg);
+return false;
-} else {
+else
-try {
+return execP(env, p.p, p.n ? v.v : v);
-listener(msg);
+case "1":
-} catch (v) {
+if (v.n != p.n)
-doExn(v);
+return false;
+else
+return execP(env, p.p, v.v);
+case "r":
+for (var fs = p.l; fs != null; fs = fs.next) {
+env = execP(env, fs.data.p, v["_" + fs.data.n]);
+if (env == false)
+return false;
+}
+return env;
+default:
+whine("Unknown Ur pattern kind" + p.c);
+}
+}
+function exec0(env, e) {
+return exec1(env, null, e);
+}
+function exec1(env, stack, e) {
+var stack, usedK = false;
+var saveEnv = function() {
+if (stack.next != null && stack.next.data.c != "<")
+stack = cons({c: "<", env: env}, stack.next);
+else
+stack = stack.next;
+};
+while (true) {
+switch (e.c) {
+case "c":
+var v = e.v;
+if (stack == null)
+return v;
+var fr = stack.data;
+switch (fr.c) {
+case "s":
+e = {c: "c", v: {v: v}};
+stack = stack.next;
+break;
+case "1":
+e = {c: "c", v: {n: fr.n, v: v}};
+stack = stack.next;
+break;
+case "f":
+fr.args[fr.pos++] = v;
+if (fr.a == null) {
+var res;
+stack = stack.next;
+if (fr.f.apply)
+res = fr.f.apply(null, fr.args);
+else if (fr.args.length == 0)
+res = fr.f();
+else if (fr.args.length == 1)
+res = fr.f(fr.args[0]);
+else if (fr.args.length == 2)
+res = fr.f(fr.args[0], fr.args[1]);
+else if (fr.args.length == 3)
+res = fr.f(fr.args[0], fr.args[1], fr.args[2]);
+else if (fr.args.length == 4)
+res = fr.f(fr.args[0], fr.args[1], fr.args[2], fr.args[3]);
+else if (fr.args.length == 5)
+res = fr.f(fr.args[0], fr.args[1], fr.args[2], fr.args[3], fr.args[4]);
+else
+whine("Native function has " + fr.args.length + " args, but there is no special case for that count.");
+e = {c: "c", v: res};
+if (usedK) return null;
+} else {
+e = fr.a.data;
+fr.a = fr.a.next;
+}
+break;
+case "a1":
+e = fr.x;
+stack = cons({c: "a2", f: v}, stack.next);
+break;
+case "a2":
+if (fr.f == null)
+whine("Ur: applying null function");
+else if (fr.f.body) {
+saveEnv();
+env = cons(v, fr.f.env);
+e = fr.f.body;
+} else {
+e = {c: "c", v: fr.f(v)};
+stack = stack.next;
+}
+break;
+case "<":
+env = fr.env;
+stack = stack.next;
+break;
+case "r":
+fr.fs["_" + fr.n] = v;
+if (fr.l == null) {
+e = {c: "c", v: fr.fs};
+stack = stack.next;
+} else {
+fr.n = fr.l.data.n;
+e = fr.l.data.v;
+fr.l = fr.l.next;
+}
+break;
+case ".":
+e = {c: "c", v: v["_" + fr.f]};
+stack = stack.next;
+break;
+case ";":
+e = fr.e2;
+stack = stack.next;
+break;
+case "=":
+saveEnv();
+env = cons(v, env);
+e = fr.e2;
+break;
+case "m":
+var ps;
+for (ps = fr.p; ps != null; ps = ps.next) {
+var r = execP(env, ps.data.p, v);
+if (r != false) {
+saveEnv();
+env = r;
+e = ps.data.b;
+break;
+}
+}
+if (ps == null)
+whine("Match failure in Ur interpretation");
+break;
+default:
+whine("Unknown Ur continuation kind " + fr.c);
 }
-}
+break;
+case "v":
+e = {c: "c", v: lookup(env, e.n)};
+break;
+case "n":
+var idx = e.n;
+e = urfuncs[idx];
+if (e.c == "t")
+e = urfuncs[idx] = e.f();
+break;
+case "s":
+stack = cons({c: "s"}, stack);
+e = e.v;
+break;
+case "1":
+stack = cons({c: "1", n: e.n}, stack);
+e = e.v;
+break;
+case "f":
+if (e.a == null)
+e = {c: "c", v: (eval(e.f))()};
+else {
+var args = [];
+stack = cons({c: "f", f: eval(e.f), args: args, pos: 0, a: e.a.next}, stack);
+if (!e.a.data.c) alert("[2] fr.f = " + e.f + "; 0 = " + e.a.data);
+e = e.a.data;
+}
+break;
+case "l":
+e = {c: "c", v: {env: env, body: e.b}};
+break;
+case "a":
+stack = cons({c: "a1", x: e.x}, stack);
+e = e.f;
+break;
+case "r":
+if (e.l == null)
+whine("Empty Ur record in interpretation");
+var fs = {};
+stack = cons({c: "r", n: e.l.data.n, fs: fs, l: e.l.next}, stack);
+e = e.l.data.v;
+break;
+case ".":
+stack = cons({c: ".", f: e.f}, stack);
+e = e.r;
+break;
+case ";":
+stack = cons({c: ";", e2: e.e2}, stack);
+e = e.e1;
+break;
+case "=":
+stack = cons({c: "=", e2: e.e2}, stack);
+e = e.e1;
+break;
+case "m":
+stack = cons({c: "m", p: e.p}, stack);
+e = e.e;
+break;
+case "e":
+e = {c: "c", v: cs({c: "wc", env: env, body: e.e})};
+break;
+case "wc":
+env = e.env;
+e = e.body;
+break;
+case "K":
+{ var savedStack = stack.next, savedEnv = env;
+e = {c: "c", v: function(v) { return exec1(savedEnv, savedStack, {c: "c", v: v}); } };}
+usedK = true;
+break;
+default:
+whine("Unknown Ur expression kind " + e.c);
 }
+}
-xhrFinished(xhr);
+}
-connect();
+function execD(e) {
-}
+return exec0(null, e);
-else {
+}
-try {
-if (xhr.status != 0)
+function exec(e) {
-servErr("Error querying remote server for messages: " + xhr.status);
+var r = exec0(null, e);
-} catch (e) { }
-}
+if (r != null && r.body != null)
-}
+return function(v) { return exec0(cons(v, r.env), r.body); };
-};
-onTimeout = function() {
-xhrFinished(xhr);
-connect();
-};
-connect();
-}
-function rv(chn, parse, k) {
-if (chn == null)
-return;
-if (chn < 0)
-whine("Out-of-bounds channel receive");
-var ch;
-if (chn >= channels.length || channels[chn] == null) {
-ch = newChannel();
-channels[chn] = ch;
-} else
-ch = channels[chn];
-var msg = dequeue(ch.msgs);
-if (msg == null) {
-enqueue(ch.listeners, function(msg) { k(parse(msg)); });
-} else {
-try {
-k(parse(msg));
-} catch (v) {
-doExn(v);
-}
-}
-}
-function sl(ms, k) {
-window.setTimeout(function() { k(null); }, ms);
-}
-function sp(e) {
-execF(e, null);
-}
-// Key events
-var uw_event = null;
-function kc() {
-return window.event ? uw_event.keyCode : uw_event.which;
-}
-// The Ur interpreter
-var urfuncs = [];
-function lookup(env, n) {
-while (env != null) {
-if (n == 0)
-return env.data;
-else {
---n;
-env = env.next;
-}
-}
-whine("Out-of-bounds Ur variable reference");
-}
-function execP(env, p, v) {
-switch (p.c) {
-case "w":
-return env;
-case "v":
-return cons(v, env);
-case "c":
-if (v == p.v)
-return env;
 else
-return false;
+return r;
-case "s":
-if (v == null)
-return false;
-else
-return execP(env, p.p, p.n ? v.v : v);
-case "1":
-if (v.n != p.n)
-return false;
-else
-return execP(env, p.p, v.v);
-case "r":
-for (var fs = p.l; fs != null; fs = fs.next) {
-env = execP(env, fs.data.p, v["_" + fs.data.n]);
-if (env == false)
-return false;
-}
-return env;
-default:
-whine("Unknown Ur pattern kind" + p.c);
-}
-}
-function exec0(env, e) {
-return exec1(env, null, e);
-}
-function exec1(env, stack, e) {
-var stack, usedK = false;
-var saveEnv = function() {
-if (stack.next != null && stack.next.data.c != "<")
-stack = cons({c: "<", env: env}, stack.next);
-else
-stack = stack.next;
-};
-while (true) {
-switch (e.c) {
-case "c":
-var v = e.v;
-if (stack == null)
-return v;
-var fr = stack.data;
-switch (fr.c) {
-case "s":
-e = {c: "c", v: {v: v}};
-stack = stack.next;
-break;
-case "1":
-e = {c: "c", v: {n: fr.n, v: v}};
-stack = stack.next;
-break;
-case "f":
-fr.args[fr.pos++] = v;
-if (fr.a == null) {
-var res;
-stack = stack.next;
-if (fr.f.apply)
-res = fr.f.apply(null, fr.args);
-else if (fr.args.length == 0)
-res = fr.f();
-else if (fr.args.length == 1)
-res = fr.f(fr.args[0]);
-else if (fr.args.length == 2)
-res = fr.f(fr.args[0], fr.args[1]);
-else if (fr.args.length == 3)
-res = fr.f(fr.args[0], fr.args[1], fr.args[2]);
-else if (fr.args.length == 4)
-res = fr.f(fr.args[0], fr.args[1], fr.args[2], fr.args[3]);
-else if (fr.args.length == 5)
-res = fr.f(fr.args[0], fr.args[1], fr.args[2], fr.args[3], fr.args[4]);
-else
-whine("Native function has " + fr.args.length + " args, but there is no special case for that count.");
-e = {c: "c", v: res};
-if (usedK) return null;
-} else {
-e = fr.a.data;
-fr.a = fr.a.next;
-}
-break;
-case "a1":
-e = fr.x;
-stack = cons({c: "a2", f: v}, stack.next);
-break;
-case "a2":
-if (fr.f == null)
-whine("Ur: applying null function");
-else if (fr.f.body) {
-saveEnv();
-env = cons(v, fr.f.env);
-e = fr.f.body;
-} else {
-e = {c: "c", v: fr.f(v)};
-stack = stack.next;
-}
-break;
-case "<":
-env = fr.env;
-stack = stack.next;
-break;
-case "r":
-fr.fs["_" + fr.n] = v;
-if (fr.l == null) {
-e = {c: "c", v: fr.fs};
-stack = stack.next;
-} else {
-fr.n = fr.l.data.n;
-e = fr.l.data.v;
-fr.l = fr.l.next;
-}
-break;
-case ".":
-e = {c: "c", v: v["_" + fr.f]};
-stack = stack.next;
-break;
-case ";":
-e = fr.e2;
-stack = stack.next;
-break;
-case "=":
-saveEnv();
-env = cons(v, env);
-e = fr.e2;
-break;
-case "m":
-var ps;
-for (ps = fr.p; ps != null; ps = ps.next) {
-var r = execP(env, ps.data.p, v);
-if (r != false) {
-saveEnv();
-env = r;
-e = ps.data.b;
-break;
-}
-}
-if (ps == null)
-whine("Match failure in Ur interpretation");
-break;
-default:
-whine("Unknown Ur continuation kind " + fr.c);
-}
-break;
-case "v":
-e = {c: "c", v: lookup(env, e.n)};
-break;
-case "n":
-e = urfuncs[e.n];
-break;
-case "s":
-stack = cons({c: "s"}, stack);
-e = e.v;
-break;
-case "1":
-stack = cons({c: "1", n: e.n}, stack);
-e = e.v;
-break;
-case "f":
-if (e.a == null)
-e = {c: "c", v: (eval(e.f))()};
-else {
-var args = [];
-stack = cons({c: "f", f: eval(e.f), args: args, pos: 0, a: e.a.next}, stack);
-if (!e.a.data.c) alert("[2] fr.f = " + e.f + "; 0 = " + e.a.data);
-e = e.a.data;
-}
-break;
-case "l":
-e = {c: "c", v: {env: env, body: e.b}};
-break;
-case "a":
-stack = cons({c: "a1", x: e.x}, stack);
-e = e.f;
-break;
-case "r":
-if (e.l == null)
-whine("Empty Ur record in interpretation");
-var fs = {};
-stack = cons({c: "r", n: e.l.data.n, fs: fs, l: e.l.next}, stack);
-e = e.l.data.v;
-break;
-case ".":
-stack = cons({c: ".", f: e.f}, stack);
-e = e.r;
-break;
-case ";":
-stack = cons({c: ";", e2: e.e2}, stack);
-e = e.e1;
-break;
-case "=":
-stack = cons({c: "=", e2: e.e2}, stack);
-e = e.e1;
-break;
-case "m":
-stack = cons({c: "m", p: e.p}, stack);
-e = e.e;
-break;
-case "e":
-e = {c: "c", v: cs({c: "wc", env: env, body: e.e})};
-break;
-case "wc":
-env = e.env;
-e = e.body;
-break;
-case "K":
-{ var savedStack = stack.next, savedEnv = env;
-e = {c: "c", v: function(v) { return exec1(savedEnv, savedStack, {c: "c", v: v}); } };}
-usedK = true;
-break;
-default:
-whine("Unknown Ur expression kind " + e.c);
-}
-}
-}
-function execD(e) {
-return exec0(null, e);
-}
-function exec(e) {
-var r = exec0(null, e);
-if (r != null && r.body != null)
-return function(v) { return exec0(cons(v, r.env), r.body); };
-else
-return r;
 }
 function execF(f, x) {
 return exec0(cons(x, f.env), f.body);
 }
 // App-specific code