ScriptCraft/examples/javascript/src/main/resources/scriptcraft/modid/index.js

import { BlockSettings, Identifier, Registry, BlockState, ActionResult, BlockItem, ItemSettings, BuiltinRegistry, CustomBlock } from 'minecraft';

console.log('hello');

const ironBlock = BuiltinRegistry.BLOCK.get(new Identifier('minecraft:iron_block'));

class MyBlock extends CustomBlock {
    constructor() {
        super(new BlockSettings(ironBlock.getMaterial(), ironBlock.getMaterialColor()));
    }

    onUse(world, blockState, blockPos, side, player, hand) {
        console.log('Block Used!');
        return ActionResult.SUCCESS;
    }
}

Registry.register(Registry.BLOCK, new Identifier('modid', 'my_block'), new MyBlock());
Registry.register(Registry.ITEM, new Identifier('modid', 'my_block'), new BlockItem(new Identifier('modid', 'my_block'), new ItemSettings()));