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interface TableOptions {  /** Padding: desired distance between column widths */  padding?: number  /** Upcase header: make the header upper case */  upcaseHeader?: boolean  /** Empty replacer: replace empty values (null, undefined, "") with a custom string */  emptyReplacer?: string}
type Datum = Record<string, any>
/** * Build a flexible table from a list of objects * @param data Data to print * @param header Desired header of the table * @param options Modify the padding, upcase the header, set empty-values replacer */export function table(data: Datum[], header: string[], opts?: TableOptions): string {  const pad = opts?.padding || 2  const upcase = opts?.upcaseHeader || false  const empty = opts?.emptyReplacer || ''
  if (!data.length || !header.length) {    return header.join(' '.repeat(pad))  }
  const validHeader = intersect(Object.keys(data[0]), header)
  if (!validHeader.length) {    throw new Error('Given header does not match any datum property!')  }
  const cols = takeCols(data, validHeader, upcase, empty)  const rows = makeRows(cols, pad)
  return rows.map(x => x.trimEnd()).join('\n')}
/*  HELPERS*/function intersect(props: string[], header: string[]) {  // keep original order of `header`  const propsSet = new Set(props)  const intersection = new Set(header.filter(prop => propsSet.has(prop)))
  return Array.from(intersection)}
function takeCols(data: Datum[], header: string[], upcase: boolean, empty: string) {  const cols: string[][] = []
  header.forEach((key, idx) => {    const keyMod = upcase ? key.toUpperCase() : key    cols.push([keyMod])
    for (const datum of data) {      if (datum.hasOwnProperty(key)) {        cols[idx].push(datum[key]?.toString() || empty)      } else {        throw new Error(`No property '${key}' in one of the given data!`)      }    }  })
  return cols}
function makeRows(cols: string[][], pad: number) {  const maxWidths = cols.map(col => Math.max(...col.map(x => x.length)))  const rowsCount = cols[0].length  const rows: string[] = []
  for (let row = 0; row < rowsCount; row++) {    rows.push(      cols        .map(col => col[row])        .reduce(          (memo, value, colIdx) => (memo += value.padEnd(maxWidths[colIdx] + pad)),          ''        )    )  }
  return rows}