3 ms·

It does not rely on an implementation detail, that is how iterators work. He's just supplied the same iterator to a function which consumes iterators... that's

• tgb 13y ago
  In fact official python docs say: "The left-to-right evaluation order of the iterables is guaranteed. This makes possible an idiom for clustering a data series into n-length groups using zip([iter(s)]n)." http://docs.python.org/2/library/functions.html#zip http://docs.python.org/2/library/functions.html#zip
• tiziano88 13y ago
  The fact that zip evaluates its arguments in order is an implementation detail. It could evaluate them in reverse order, in which case this code would not behave as expected.
  • StavrosK 13y ago
    That's what I meant, thanks for clarifying. It does seem that the zip() docs make a guarantee of left-to-right evaluation, though, so my apprehension proved unfounded.