var QuillDeltaToHtmlConverter = require('quill-delta-to-html').QuillDeltaToHtmlConverter;

// TypeScript / ES6:
// import { QuillDeltaToHtmlConverter } from 'quill-delta-to-html'; 

var deltaOps =  [
    {insert: "Hello\n"},
    {insert: "This is colorful", attributes: {color: '#f00'}}
];

var cfg = {};

var converter = new QuillDeltaToHtmlConverter(deltaOps, cfg);

var html = converter.convert(); 

converter.beforeRender(function(groupType, data){
    // ... generate your own html 
    // return your html
});
converter.afterRender(function(groupType, htmlString){
    // modify if you wish
    // return the html
});

html = converter.convert();

{
    insert: {
        type: '' // one of 'text' | 'image' | 'video' | 'formula',
        value: '' // some string value  
    }, 
    attributes: {
        // ... quill delta attributes 
    }
}

inlineStyles: {
   font: {
      'serif': 'font-family: Georgia, Times New Roman, serif',
      'monospace': 'font-family: Monaco, Courier New, monospace'
   },
   size: {
      'small': 'font-size: 0.75em',
      'large': 'font-size: 1.5em',
      'huge': 'font-size: 2.5em'
   },
   indent: (value, op) => {
      var indentSize = parseInt(value, 10) * 3;
      var side = op.attributes['direction'] === 'rtl' ? 'right' : 'left';
      return 'padding-' + side + ':' + indentSize + 'em';
   },
   direction: (value, op) => {
      if (value === 'rtl') {
         return 'direction:rtl' + ( op.attributes['align'] ? '' : '; text-align: inherit' );
      } else {
         return '';
      }
   }
};

let ops = [
    {insert: {'my-blot': {id: 2, text: 'xyz'}}, attributes: {renderAsBlock: true|false}}
];

let converter = new QuillDeltaToHtmlConverter(ops);

// customOp is your custom blot op
// contextOp is the block op that wraps this op, if any. 
// If, for example, your custom blot is located inside a list item,
// then contextOp would provide that op. 
converter.renderCustomWith(function(customOp, contextOp){
    if (customOp.insert.type === 'my-blot') {
        let val = customOp.insert.value;
        return `<span id="${val.id}">${val.text}</span>`;
    } else {
        return 'Unmanaged custom blot!';
    }
});

html = converter.convert();

{
    insert: {
        type: string //whatever you specified as key for insert, in above example: 'my-blot'
        value: any // value for the custom blot  
    }, 
    attributes: {
        // ... any attributes custom blot may have
    }
}

let groupedOps = converter.getGroupedOps();