code: function Record(line, header) {
      // Returns a VCF record.
      //
      // `line` - a line of the VCF file that represents an individual record.
      // `header` - the parsed VCF header.
      var vals = line.split('\t');
      this.initializeRecord(vals, header);
  
      if (this.CHROM)   this.CHROM   = parseChrom(this.CHROM, header);
      if (this.POS)     this.POS     = parsePos(this.POS, header);
      if (this.ID)      this.ID      = parseId(this.ID, header);
      if (this.REF)     this.REF     = parseRef(this.REF, header);
      if (this.ALT)     this.ALT     = parseAlt(this.ALT, header);
      if (this.QUAL)    this.QUAL    = parseQual(this.QUAL, header);
      if (this.FILTER)  this.FILTER  = parseFilter(this.FILTER, header);
      if (this.INFO)    this.INFO    = parseInfo(this.INFO, header);
      if (this.FORMAT)  this.FORMAT  = parseFormat(this.FORMAT, header);
      this.__KEY__ = genKey(this, header);
  
      for (var idx = 0; idx < header.sampleNames.length; idx++) {
        var sampleName = header.sampleNames[idx],
            sample = this[sampleName];
        if (sample) {
          this[sampleName] = parseSample(sample, this.FORMAT, header);
        }
      }
    }
docs: //////////////////////////////////////////////////////////////////// Below: initializing Records and parsing their constituent data.  // ////////////////////////////////////////////////////////////////////