polymer - Template repeat inside template repeat - get all item names -

i'm trying realise website using polymer 1.0. have custom element my-greeting template repeats inside.

what do, , don't find how this, string called target looks :

/constantpath/folder1/aaa.jpg /constantpath/folder1/bbb.jpg /constantpath/folder2/aaa.jpg /constantpath/folder2/bbb.jpg 

so general string : /constantpath/{{repeat1.id}}/{{repeat2.id}}.jpg

how can ??

here code :

<dom-module id="my-greeting">   <template>     <template is="dom-repeat" items="{{repeat1}}">       <template is="dom-repeat" items="{{repeat2}}">         target : <iron-image src="target"></iron-image>       </template>     </template>   </template>    <script>     polymer({       is: 'my-greeting',       ready: function() {         this.repeat1 = [             {id: 'folder1'},             {id: 'folder2'}         ];         this.repeat2 = [             {id: 'aaa'},             {id: 'bbb'}         ];       }     }     );   </script> 

thanks.

here go:

<dom-module id="my-greeting">   <template>     <template is="dom-repeat" items="{{repeat1}}" as="folderone">       <template is="dom-repeat" items="{{repeat2}}" as="foldertwo">         target : <span>{{gettarget(folderone, foldertwo)}}</span></br>       </template>     </template>   </template>    <script>     polymer({       is: 'my-greeting',       ready: function() {         this.repeat1 = [             {id: 'folder1'},             {id: 'folder2'}         ];         this.repeat2 = [             {id: 'aaa'},             {id: 'bbb'}         ];       },       gettarget: function(folderone, foldertwo){         return "/constantpath/"+folderone.id+"/"+foldertwo.id;       },     }     );   </script> </dom-module>