Debugging the Difference Engine

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Reproducing it

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# Run the simulator for 40 turns of the crank.
npx difference-engine --turns 40 --trace > trace.log
grep -n "carry" trace.log | head -5

The fix

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- if (wheel.value > 9) wheel.carry = true;
+ if (wheel.value > 9) {
+   wheel.value -= 10;
+   wheel.carry = true;
+ }

The printout

Excepteur sint occaecat cupidatat non proident. The printout uses its own stylesheet:

@media print {
  .table {
    font-variant-numeric: tabular-nums;
    border-collapse: collapse;
  }
}

<!doctype html>
<table class="table">
  <tr><td>1</td><td>2</td></tr>
</table>

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