<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Jun 4, 2016, at 13:25, Ben Darnell <<a href="mailto:ben@bendarnell.com" class="">ben@bendarnell.com</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><span style="font-family: Menlo-Regular; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;" class="">If things are so sensitive to minor changes in timing, doesn't that set the bar impossibly high for interoperability?<span class="Apple-converted-space"> </span></span></div></blockquote></div><br class=""><div class="">The sensitivity is not to changes in <i class="">timing</i> - i.e. when the wall-clock runs, or ordering of non-deterministically ordered events - but rather to <i class="">reentrancy</i> - whether certain things complete synchronously while the caller is still on the stack and can depend on them having done so upon return.</div><div class=""><br class=""></div><div class="">The recommended way of writing tests within Twisted these days depends heavily on `.callback´ synchronously resolving a Deferred, which is what adding a call_soon breaks.</div><div class=""><br class=""></div><div class="">-glyph</div><div class=""><br class=""></div><div class=""><br class=""></div></body></html>