jimbocoder · June 24, 2015 02:36 · Jun 24, 2015
diff --git a/php-compose.php b/php-compose.php
@@ -0,0 +1,27 @@
+function compose() {
+    $fxns = func_get_args();
+    $outer = function($identity) { return $identity; };
+    while($f = array_pop($fxns)) {
+        if ( !is_callable($f) ) {
+            throw new \Exception('This should be a better exception.');
+        }
+        $outer = function() use($f, $outer) {
+            return $f(call_user_func_array($outer, func_get_args()));
+        };
+    }
+    return $outer;
+}
+
+$password = 'PASSWORD';
+
+$rot13 = compose('str_rot13');
+// Hide our password from kid sister:
+print $rot13($password) . "\n";
+
+$doubleRot13 = compose($rot13, 'str_rot13');
+// Whoops, overshot that one:
+print $doubleRot13($password) . "\n";
+
+$uberHasher = compose('sha1', 'md5', 'crc32');
+// A REALLY SUPER ULTIMATE SECURE HASH:
+print $uberHasher($password) . "\n";