<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></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 Apr 3, 2017, at 7:24 AM, Ricardo Parada via swift-evolution <<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><meta http-equiv="Content-Type" content="text/html charset=utf-8" class=""><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">By the way, does anybody know why the proposed syntax require a leading period for the key path?<div class=""><br class=""></div><div class=""><font face="Menlo" class="">#keyPath(Family, <font color="#ff0000" class="">.</font>pets.first)</font></div></div></div></blockquote><br class=""></div><div>Grammatically, it's a series of postfix expression components, including property accesses `.foo`, subscripts `[bar]`, and optional operators `?` and `!`. The grammar is more uniform requiring the dot.</div><div><br class=""></div><div>-Joe</div><br class=""></body></html>