Lambdaheads: Unterschied zwischen den Versionen

← Zum vorherigen Versionsunterschied Zum nächsten Versionsunterschied →

VisuellWikitext

@@ Zeile 21: / Zeile 21: @@
 == nächster regulärer Termin ==
-Termin: Mo, '''2013-06-18''' ab 20:00 Uhr in der Bibliothek [[Lage|im Metalab]]
+Termin: Mo, '''2013-07-16''' ab 20:00 Uhr in der Bibliothek [[Lage|im Metalab]]
 === Programm ===
-The first two workshops are guaranteed to happen. Bring your laptops.
+generators in future ECMAscript
-* gather/take construct reimplemented for JS
-* functional and higher order primitives as expressed through Perlito.js
-* perhaps Roland will show up with his [http://www.meetup.com/viennajs/events/16286766/ type safety ideas]
 === Teilnehmer ===
@@ Zeile 35: / Zeile 31: @@
 * [[Benutzer:Daxim]]
 * [[Benutzer:Epsilon.halbe|ε/2]]
+* http://www.meetup.com/viennajs/events/126593272/
 <!--
@@ Zeile 73: / Zeile 70: @@
 = Frühere Events =
+== 2013-06-18 ==
+comb, one of the opposites of join (the other one is split)
+<pre>
+String.prototype.comb = function(re) {
+    // lol type conversion the hacky way
+    re = ('' + re)              // now it's a string
+        .replace(/^\//, '')     // hack off leading
+        .replace(/\/$/, '');    // trailing delimiter
+    // no interpolation, no sigils, no sprintf
+    return eval('this.match(/(' + re + ')+/g)');
+}
+</pre>
+gather/take construct reimplemented for JS - a replacement for the idiom of declaring a collecting variable and pushing into it occasionally http://perl6.wikia.com/wiki/Gather
+<pre>
+function gather(fn) {
+    var guard = new Array;
+    var take = function (items) {
+        guard = guard.concat(items);
+    };
+    fn(take);
+    return guard;
+};
+console.log(
+    gather(function(take) {
+        for (var i = 0; i <= 10; i++) {
+            if (i % 2) {
+                take(i);
+            }
+        }
+    })
+)
+var arr = [];
+for (var i = 0; i <= 10; i++) {
+    if (i % 2) {
+        arr.push(i);
+    }
+}
+</pre>
+Haskell example is incomplete
+<pre>
+gather x = foldr (:) [] x
+main = print $ gather [0..10]
+</pre>
+reimplementation of List::Gen::by http://p3rl.org/List::Gen#by-NUM-LIST (no generators, just list transformation)
+<pre>
+function by(n, a) {
+    var r = new Array;
+    while(a.length) {
+        r.push(a.splice(0, n));
+    };
+    console.log(a);
+    return r;
+};
+function by2(n, a) {
+    return a.length ? [a.slice(0, n)].concat(by2(n, a.slice(n))) : [];
+}
+console.log( by2(5, [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15]) );
+console.log( by2(5, [1,2,3,4,5,6,7,8,9,10,11,12,13,14]) );
+console.log( by2(5, [1,2,3,4]) );
+console.log( by2(5, []) );
+</pre>
+<pre>
+// contrib by intval
+// divides array into equal arrays, each of size n
+function by(n, arr) {
+    function byby(n, arr, accum) {
+        if(arr.length < 1) {
+            return accum;
+        }
+        var head = [arr.slice(0,n)];
+        var tail = arr.slice(n);
+        return byby(n, tail, accum.concat(head));
+    }
+    return byby(n, arr, []);
+}
+console.log( by(5, [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15]) );
+console.log( by(5, [1,2,3,4,5,6,7,8,9,10,11,12,13,14]) );
+console.log( by(5, [1,2,3,4]) );
+console.log( by(25, []) );
+</pre>
 == 2013-05-21 ==