The repeat block is one of our core blocks. Here's the json definition, which you can also
find in the blocks folder of the repository.
{
"type": "controls_repeat_ext",
"message0": "%{BKY_CONTROLS_REPEAT_TITLE}",
"args0": [{
"type": "input_value",
"name": "TIMES",
"check": "Number"
}],
"message1": "%{BKY_CONTROLS_REPEAT_INPUT_DO} %1",
"args1": [{
"type": "input_statement",
"name": "DO"
}],
"previousStatement": null,
"nextStatement": null,
"style": "loop_blocks",
"tooltip": "%{BKY_CONTROLS_REPEAT_TOOLTIP}",
"helpUrl": "%{BKY_CONTROLS_REPEAT_HELPURL}"
},
If you want XML for those blocks, you can create the block combination in your Blockly workspace (or in the playground) and then export to XML. Here it is:
<block type="controls_repeat_ext" >
<value name="TIMES">
<block type="math_number">
<field name="NUM">10</field>
</block>
</value>
</block>
</xml>