[KLUG Programming] PHP arrays vs. structures

[Adam Tauno Williams]

> > This solves my problems 
> A common PHP phrase
> > since the structures I have to deal with never
> > use numeric keys, so if the first key is 0 then it is an array,
> > otherwise it must be a structure (keys are strings).  So I'm just lucky
> > (for once!) in this case.
> It's implicit, which means that unless the keys are explicitly set as
> strings, you can refer to them numerically.  That tidbit can be
> extremely helpful (because so much code doesn't explicitly set the
> key).  In your case the check code you were looking for is not even
> necessary.

But other languages (C, etc...) as well as documents (XML, etc...) do
clearly distinguish between an array and a structure.  Using the numeric
key = array hack I've constructed...


    function wrap($value) {
      $this->traceMessage('@OGoDocument:wrap');
      switch(gettype($value)) {
        case 'boolean':
          $this->traceMessage('@OGoDocument:wrap.boolean');
          $value = new XML_RPC_value($value, 'boolean');
         break;
        case 'integer':
          $this->traceMessage('@OGoDocument:wrap.integer');
          $value = new XML_RPC_value($value, 'int');
         break;
        case 'double':
          $this->traceMessage('@OGoDocument:wrap.double');
          $value = new XML_RPC_value($value, 'double');
         break;
        case 'string':
          $this->traceMessage('@OGoDocument:wrap.string');
          $value = new XML_RPC_value($value, 'string');
         break;
        case 'array':
          $this->traceMessage('@OGoDocument:wrap.array');
          $a = array();
          reset($value);
          if (key($value) == '0') {
            //array
            $this->traceMessage('@OGoDocument:wrap.array.array');
            $a_type = 'array';
            foreach ($value as $v)
               array_push($a, $this->wrap($v));
           } else {
               //struct
               $this->traceMessage('@OGoDocument:wrap.struct'); 
               $a_type = 'struct';
               foreach ($value as $k => $v)
                 $a[$k] = $this->wrap($v);
             }
          $value = new XML_RPC_value($a, $a_type);
         break;
        case 'object':
          $this->traceMessage('@OGoDocument:wrap.object');
          /// NOT SUPPORTED
         break;
        case 'resource':
          $this->traceMessage('@OGoDocument:wrap.resource');
          /// NOT SUPPORTED
         break;
        case 'NULL':
          $this->traceMessage('@OGoDocument:wrap.NULL');
          /// NOT SUPPORTED
         break;
       }
      return $value;
     }

... which seems to be able to turn PHP structures into documents that
can be transported to a web service.