decode.php

php/decode.php

@@ -0,0 +1,69 @@
+<?php
+
+/**
+ * Simple php equivalent of Oracle's decode()
+ *
+ * It can be used as simple oneline-alternative to switch or if operators in many
+ * cases without difficult logic. For example, get string mnemocode of some value:
+ *
+ * echo 'State: '.decode($state, 0, 'disabled', 1, 'enabled', 'unknown');
+ *
+ * will output:
+ * 'State: disabled' if $state === 0
+ * 'State: enabled' if $state === 1
+ * 'State: unknown' in other cases
+ *
+ * This is how decode() works:
+ * 1)   Store first argument separately from other ones to compare them with it
+ * 2)   Reduce and reindex array of arguments from 0
+ * 3)   Detect default value:
+ * 3.1) If count of fresh args array is odd (which means that decode() was called
+ *      with even args count) then the last known argument is default result.
+ *      We also need to reduce and reindex args array here.
+ * 3.2) If count is even, then default result === null.
+ * 4)   The rest of args processing this way:
+ *    - every even argument (n, n+2, n+4,...) is possible value;
+ *    - every odd arg (n+1, n+3, n+5,...) is result for previous arg.
+ *
+ * @see https://docs.oracle.com/cd/B19306_01/server.102/b14200/functions040.htm
+ * @see https://gist.github.com/anthonyaxenov/510c92931e2cfa63633d7ab1e4465133
+ * @author Anthony Axenov
+ * @return mixed
+ */
+function decode()
+{
+    $args = func_get_args();
+    $expression = $args[0];
+    unset($args[0]);
+    $args = array_values($args);
+    if (count($args) % 2 !== 0) {
+        $default = $args[count($args) - 1];
+        unset($args[count($args) - 1]);
+        $args = array_values($args);
+    } else {
+        $default = null;
+    }
+    for ($i = 0; $i < count($args); $i += 2) {
+        if ($expression === $args[$i] && isset($args[$i + 1])) {
+            return is_callable($args[$i + 1]) ? call_user_func($args[$i + 1]) : $args[$i + 1];
+        }
+    }
+    return $default;
+}
+
+// usage:
+$somevar = 'function';
+$anything = 'Lorem ipsum dolor sit amet';
+$result = decode($somevar,                   // 0
+    true      , 'decode(): boolean true',    // 1
+    0         , 'decode(): int zero',        // 2
+    '0'       , 'decode(): string zero',     // 3
+    'string'  , 'decode(): just string',     // 4
+    'function', function() use ($anything) { // 5
+        // bla-bla-bla some logic here
+        $anything = explode(' ', $anything);
+        return 'Hey, this is '.print_r($anything, true);
+    },
+    'decode(): default result'               // 6 -- comment this line to get null
+);
+var_dump($result);