<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=""><div><blockquote type="cite" class=""><div class=""><span style="font-family: Helvetica; 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="">It would mean for Apple (and others who'd distribute compiled frameworks) to maintain several code bases of the same framework given that they would need to maintain backward compatibility and hence wouldn't be able to use new language features, etc. It's IMHO not that much about the technical constraint of having multiple binaries within the framework bundle as much as maintaining the code in a way that would compile under all Swift versions you'd like to support.</span></div></blockquote></div>I haven't spend much time thinking about the implications, but wouldn't it be feasible to freeze old frameworks completely when a new Swift version is added?<div class="">After all, bundled code isn't updated at all, so I see no downside here — actually, it only adds flexibility that could be utilised when critical bugs are discovered.</div><div class=""><br class=""></div><div class="">I wouldn't expect that I can mix language and framework versions freely.</div></body></html>