lit-html with dynamic tags

preHTML

import { html } from '@polymer/lit-element/src/lit-element';

let string: string;
let valuesLength: number;

export function preHTML (strings: TemplateStringsArray, ...values: any[]) {
  const newStrings: string[] = [];
  const newValues: any[] = [];

  valuesLength = values.length;

  for (var i = 0; i < strings.length; i += 1) {
    string = strings[i];

    if (string[string.length - 1] === '<') {
      newStrings.push(string + values[i] + strings[++i]);
      newValues.push(values[i]);
    } else if (string[string.length - 2] === '<' && string[string.length - 1] === '/') {
      newStrings.push((string = string + values[i] + strings[++i]));
    } else {
      newStrings.push(string);
      newValues.push(values[i]);
    }
  }

  return html(newStrings as any, ...newValues);
}