Open intervals in programming are rare.
For example, if it's impossible to divide by 0 and infinity, the valid intervals for divisor are: (-inf, 0) and (0, +inf). Hence we include however small numbers but not zero. And however large numbers, but not infinity.
The major source of fencepost errors is a confusion between closed and half-open intervals.
If you're aware what intervals do you use in each loop, you'll reduce number of errors significantly.
Also, note that Edsger W. Dijkstra was a famous proponent of half-open intervals and arrays starting at zero index.
In his famous paper, he enumerates half-open, half-closed, closed and open intervals and offers to choose best suited for programming:
a) 2 ≤ i < 13 b) 1 < i ≤ 12 c) 2 ≤ i ≤ 12 d) 1 < i < 13
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