3 files changed, 20 insertions(+), 2 deletions(-)

M README.md
M src/Data.php
M tests/PrimitivesTest.php

@@ 18,8 18,8 @@ Work in progress.
 * `bool`: **Boolean** (bool)
 * `enum`: Not yet implemented, use **UInt**.
 * `string`: **Str** (string)
-* `data<length>`: Not yet implemented.
-* `data`: **Data**
+* `data<length>`: extend **Data**, defining BYTES
+* `data`: **Str**
 * `void`: **Nothing**
 
 All primitive types provide the following methods, which can be used as follows.


@@ 32,4 32,8 @@ $dayNumber->set(365); // Mutator
 $mess = $dayNumber->mess(); // Convert into BARE message format.
 $day = new U16($mess); // Constructor mutates the $mess parameter
 $day->get(); // Accessor -- returns 365
+class Data2 extends \BareMess\Data {public const BYTES = 2;}
+$mess = $day->mess();
+$data2 = new Data2($mess);
+$data2->get(); // Will be equivalent to $day->mess().
 ```

@@ 7,6 7,15 @@ abstract class Data
     use Mutatable;
     private string $value = '';
 
+    public function __construct(string & $mess = null)
+    {
+        if ($mess === null){
+            return;
+        }
+        $this->value = substr($mess, 0, get_called_class()::BYTES);
+        $mess = substr($mess, get_called_class()::BYTES);
+    }
+
     public function set(string $value)
     {
         return $this->value = substr($value, 0, get_called_class()::BYTES);

@@ 49,6 49,11 @@ class PrimitivesTest extends TestCase
         $this->assertEquals($value, $pk3->set($lies));
         $this->assertNotEquals($lies, $pk3->get());
         $this->assertEquals($value, $pk3->get());
+
+        $mess = $pk3->mess();
+        $pk4 = new PublicKey($mess);
+        $this->assertEquals('', $mess);
+        $this->assertEquals($pk3->get(), $pk4->get());
     }
 
     public function testEnum()