On Wed, Aug 26, 2015 at 3:00 PM, Guido van Rossum <guido@python.org> wrote:

Note that the current text of the PEP has a flag named 'first' whose

definition is the opposite; but the plan is to switch to fold=0. I decided to establish the origin of the term "fold" before editing the PEP. The credit for introducing the term "fall-backward fold" in computing goes to Paul Eggert of UCLA who used it in various discussions related to the C language standard that culminated in a defect report #139 [1]. However, apparently, the idea goes back to 1917 Germany. As Paul Eggert explained in private correspondence, """ fold=0 and fold=1 is like the longstanding German standard for expressing times as strings, which uses "A" and "B" to distinguish time stamps that would otherwise be ambiguous. If I understand things correctly, normally fold=0, but you can have fold=1 when time stamps are repeated. For more about the German standard, you can start with the Wikipedia description here: [2] """ [1]: http://www.open-std.org/jtc1/sc22/wg14/docs/rr/dr_136.html [2]: https://de.wikipedia.org/wiki/Sommerzeit#Offizielle_Regelung_der_Zeitumstell...