code: function checkTypeSelector(i) {
    if (i >= tokensLength) return 0;
  
    const start = i;
    let l;
  
    if (l = checkNamePrefix(i)) i += l;
  
    if (l = checkIdentOrInterpolation(i)) i += l;
    else return 0;
  
    return i - start;
  }
docs: Check if token is part of a type selector
  @param {number} i Token's index
  @return {number} Type selector's length