Nicholas Jones

#!/usr/bin/env node
// carsum: summarize price/mileage of used-car listings from a CSV file or stdin.
import { readFileSync } from 'node:fs';

function parseLine(line) {
  const fields = [];
  let cur = '', inQuotes = false;
  for (let i = 0; i < line.length; i++) {
    const c = line[i];
    if (inQuotes && c === '"' && line[i + 1] === '"') { cur += '"'; i++; }
    else if (c === '"') inQuotes = !inQuotes;
    else if (c === ',' && !inQuotes) { fields.push(cur); cur = ''; }
    else cur += c;
  }
  fields.push(cur);
  return fields.map((f) => f.trim());
}

const toNumber = (s) => (/\d/.test(s