<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="">Hi Dimitri,<div class=""><br class=""></div><div class="">You may be interested in taking a look at a proposal I introduced about a year ago which was deferred. Memberwise initialization is a topic we intend to revisit eventually. This may happen in phase 2 of the Swift 4 effort, or may not happen until Swift 5.</div><div class=""><br class=""></div><div class=""><a href="https://github.com/apple/swift-evolution/blob/master/proposals/0018-flexible-memberwise-initialization.md" class="">https://github.com/apple/swift-evolution/blob/master/proposals/0018-flexible-memberwise-initialization.md</a></div><div class=""><br class=""></div><div class="">Matthew</div><div class=""><br class=""><div><blockquote type="cite" class=""><div class="">On Feb 15, 2017, at 9:38 AM, Dimitri Racordon 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="">
<div class="">Hello community!</div>
<div class=""><br class="">
</div>
<div class="">While writing a Swift introduction tutorial for students, I’ve been stumbling upon the rules for struct default and memberwise initializers.</div>
<div class="">I failed to find explanations in Apple’s language guide, but as far as I could observe, I think the rules don’t fit interesting use-cases.</div>
<div class=""><br class="">
</div>
<div class="">Here are the cases that I was able to identify (I hope you don’t mind millennials and their obligatory Pokemon references):</div>
<div class=""><br class="">
</div>
<div class="">First, as documented in Apple’s guide, structs that doesn’t define any initializer and have no default values receive a memberwise initializer:</div>
<div class=""><br class="">
</div>
<div class="">
<div style="margin: 0px; line-height: normal; font-family: Menlo; color: rgb(181, 192, 203);" class="">
<div style="margin: 0px; font-size: 11px; line-height: normal;" class="">
<span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">typealias</span><span style="font-variant-ligatures: no-common-ligatures" class=""> Species = (number:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Int</span><span style="font-variant-ligatures: no-common-ligatures" class="">, name:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">String</span><span style="font-variant-ligatures: no-common-ligatures" class="">)</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; min-height: 13px;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""></span><br class="">
</div>
<div style="margin: 0px; font-size: 11px; line-height: normal;" class="">
<span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">struct</span><span style="font-variant-ligatures: no-common-ligatures" class=""> Pokemon {</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">let</span><span style="font-variant-ligatures: no-common-ligatures" class=""> species:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Species</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">var</span><span style="font-variant-ligatures: no-common-ligatures" class=""> level:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Int</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal;" class="">
<span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(4, 51, 255);" class="">var</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> nickname: </span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(52, 149, 175);" class="">String</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class="">}</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; min-height: 13px;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""></span><br class="">
</div>
<div style="margin: 0px; font-size: 11px; line-height: normal;" class="">
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">let</span><span style="font-variant-ligatures: no-common-ligatures" class=""> bulby =
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Pokemon</span><span style="font-variant-ligatures: no-common-ligatures" class="">(species: (001,
</span><span style="font-variant-ligatures: no-common-ligatures; color: #b4261a" class="">"Bulbasaur"</span><span style="font-variant-ligatures: no-common-ligatures" class="">), level: 1, nickname:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #b4261a" class="">"bulby"</span><span style="font-variant-ligatures: no-common-ligatures" class="">)</span></div>
</div>
</div>
</div>
<div style="margin: 0px; font-size: 14px; line-height: normal; font-family: Menlo; color: rgb(181, 192, 203);" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""><br class="">
</span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures;" class="">Structs that define a default value for all their properties receive a default initializer:</span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures;" class=""><br class="">
</span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures;" class="">
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">struct</span><span style="font-variant-ligatures: no-common-ligatures" class=""> Pokemon {</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">let</span><span style="font-variant-ligatures: no-common-ligatures" class=""> species:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Species</span><span style="font-variant-ligatures: no-common-ligatures" class=""> = (001,
</span><span style="font-variant-ligatures: no-common-ligatures; color: #b4261a" class="">"Bulbasaur"</span><span style="font-variant-ligatures: no-common-ligatures" class="">)</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">var</span><span style="font-variant-ligatures: no-common-ligatures" class=""> level:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Int</span><span style="font-variant-ligatures: no-common-ligatures" class=""> = 1</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">var</span><span style="font-variant-ligatures: no-common-ligatures" class=""> nickname:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">String</span><span style="font-variant-ligatures: no-common-ligatures" class=""> =
</span><span style="font-variant-ligatures: no-common-ligatures; color: #b4261a" class="">"bulby"</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class="">}</span></div>
</span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures;" class=""><br class="">
</span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures;" class="">
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo; color: rgb(52, 149, 175);" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""><span style="font-variant-ligatures: no-common-ligatures; color: rgb(4, 51, 255);" class="">let</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> bulby <span style="" class="">=</span> </span>Pokemon</span><span style="font-variant-ligatures: no-common-ligatures;" class="">()</span></div>
</span></div>
<div class=""><br class="">
</div>
<div class="">Now digging a bit deeper, I noticed that they also seem to receive an initializer for their non-constant properties:</div>
<div class=""><br class="">
</div>
<div class="">
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">let</span><span style="font-variant-ligatures: no-common-ligatures" class=""> bulby =
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Pokemon</span><span style="font-variant-ligatures: no-common-ligatures" class="">(level: 1, nickname:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #b4261a" class="">"bulby"</span><span style="font-variant-ligatures: no-common-ligatures" class="">)</span></div>
</div>
<div class=""><span style="font-family: Menlo; font-size: 11px; font-variant-ligatures: no-common-ligatures;" class=""><br class="">
</span></div>
<div class="">If no value is provided for one (or several) of its variable properties, they receives an initializer for all their variable properties:</div>
<div class=""><br class="">
</div>
<div class="">
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">struct</span><span style="font-variant-ligatures: no-common-ligatures" class=""> Pokemon {</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">let</span><span style="font-variant-ligatures: no-common-ligatures" class=""> species:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Species</span><span style="font-variant-ligatures: no-common-ligatures" class=""> = (001,
</span><span style="font-variant-ligatures: no-common-ligatures; color: #b4261a" class="">"Bulbasaur"</span><span style="font-variant-ligatures: no-common-ligatures" class="">)</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">var</span><span style="font-variant-ligatures: no-common-ligatures" class=""> level:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Int</span><span style="font-variant-ligatures: no-common-ligatures" class=""> = 1</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">var</span><span style="font-variant-ligatures: no-common-ligatures" class=""> nickname:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">String</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class="">}</span></div>
</div>
<div class=""><br class="">
</div>
<div class="">
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">let</span><span style="font-variant-ligatures: no-common-ligatures" class=""> bulby =
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Pokemon</span><span style="font-variant-ligatures: no-common-ligatures" class="">(level: 1, nickname:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #b4261a" class="">"bulby"</span><span style="font-variant-ligatures: no-common-ligatures" class="">)</span></div>
</div>
<div class=""><br class="">
</div>
<div class="">Finally, if they're given a default value for their variable properties but not for their constant properties, they receive the full memberwise initializer only:</div>
<div class=""><br class="">
</div>
<div class="">
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures; color: rgb(4, 51, 255);" class="">struct</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> Pokemon {</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(4, 51, 255);" class="">let</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> species: </span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(52, 149, 175);" class="">Species</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(4, 51, 255);" class="">var</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> level: </span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(52, 149, 175);" class="">Int</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> =
1</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(4, 51, 255);" class="">var</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> nickname: </span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(52, 149, 175);" class="">String</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> = </span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(180, 38, 26);" class="">"bulby"</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures;" class="">}</span></div>
</div>
<div class=""><br class="">
</div>
<div class="">
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">let</span><span style="font-variant-ligatures: no-common-ligatures" class=""> bulby =
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Pokemon</span><span style="font-variant-ligatures: no-common-ligatures" class="">(species: (001,
</span><span style="font-variant-ligatures: no-common-ligatures; color: #b4261a" class="">"Bulbasaur"</span><span style="font-variant-ligatures: no-common-ligatures" class="">), level: 1, nickname:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #b4261a" class="">"bulby"</span><span style="font-variant-ligatures: no-common-ligatures" class="">)</span></div>
</div>
<br class="">
<div class="">If the two extreme cases sounds perfectly valid to me (no default value vs all default values), the mixed situations do not.</div>
<div class="">In particular, it seems strange that a struct without a default value for its constant property, but one for all its variable properties receives the memberwise initializer only. I guess that would be a common “mixed situation” case, yet the provided
initializer is actually useless.</div>
<div class=""><br class="">
</div>
<div class="">Receiving the full memberwise initializer is fine, but I would also expect to receive some kind of "partial memberwise” initializer for all properties (constants or variables) that are not defined:</div>
<div class=""><br class="">
</div>
<div class="">
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures; color: rgb(4, 51, 255);" class="">struct</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> Pokemon {</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(4, 51, 255);" class="">let</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> species: </span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(52, 149, 175);" class="">Species</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(4, 51, 255);" class="">var</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> level: </span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(52, 149, 175);" class="">Int</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> =
1</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures;" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(4, 51, 255);" class="">var</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> nickname: </span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(52, 149, 175);" class="">String</span><span style="font-variant-ligatures: no-common-ligatures;" class=""> = </span><span style="font-variant-ligatures: no-common-ligatures; color: rgb(180, 38, 26);" class="">"bulby"</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures;" class="">}</span></div>
</div>
<div class=""><br class="">
</div>
<div class=""><span style="font-family: Menlo; font-size: 11px; font-variant-ligatures: no-common-ligatures; color: rgb(4, 51, 255);" class="">let</span><span style="font-family: Menlo; font-size: 11px; font-variant-ligatures: no-common-ligatures;" class=""> bulby
= </span><span style="font-family: Menlo; font-size: 11px; font-variant-ligatures: no-common-ligatures; color: rgb(52, 149, 175);" class="">Pokemon</span><span style="font-family: Menlo; font-size: 11px; font-variant-ligatures: no-common-ligatures;" class="">(species:
(001, </span><span style="font-family: Menlo; font-size: 11px; font-variant-ligatures: no-common-ligatures; color: rgb(180, 38, 26);" class="">"Bulbasaur”</span><span style="font-family: Menlo; font-size: 11px; font-variant-ligatures: no-common-ligatures;" class="">)</span><span style="font-family: Menlo; font-size: 11px; font-variant-ligatures: no-common-ligatures;" class="">)</span></div>
<div class="">
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo; color: rgb(52, 149, 175);" class="">
<span style="font-variant-ligatures: no-common-ligatures" class="">print</span><span style="font-variant-ligatures: no-common-ligatures;" class="">(</span><span style="font-variant-ligatures: no-common-ligatures" class="">bulby</span><span style="font-variant-ligatures: no-common-ligatures;" class="">)</span></div>
</div>
<div class=""><span style="font-family: Menlo; font-size: 11px; font-variant-ligatures: no-common-ligatures;" class="">
<div style="margin: 0px; line-height: normal; color: rgb(0, 143, 0);" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">// Prints "Pokemon(species: (1, "Bulbasaur"), level: 1, nickname: "bulby")"</span></div>
</span></div>
<div class=""><span style="font-family: Menlo; font-size: 11px; font-variant-ligatures: no-common-ligatures;" class=""><br class="">
</span></div>
<div class="">Besides, that would avoid some tedious initializer definitions. Indeed, If I want to get the desired result, I have to write this kind of initializer:</div>
<div class=""><br class="">
</div>
<div class="">
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">struct</span><span style="font-variant-ligatures: no-common-ligatures" class=""> Pokemon {</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">let</span><span style="font-variant-ligatures: no-common-ligatures" class=""> species:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Species</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">var</span><span style="font-variant-ligatures: no-common-ligatures" class=""> level:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Int</span><span style="font-variant-ligatures: no-common-ligatures" class=""> = 1</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">var</span><span style="font-variant-ligatures: no-common-ligatures" class=""> nickname:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">String</span><span style="font-variant-ligatures: no-common-ligatures" class=""> =
</span><span style="font-variant-ligatures: no-common-ligatures; color: #b4261a" class="">"bulby"</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo; min-height: 13px;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""></span><br class="">
</div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">init</span><span style="font-variant-ligatures: no-common-ligatures" class="">(species:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Species</span><span style="font-variant-ligatures: no-common-ligatures" class="">, level:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Int</span><span style="font-variant-ligatures: no-common-ligatures" class="">? =
</span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">nil</span><span style="font-variant-ligatures: no-common-ligatures" class="">, nickname:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">String</span><span style="font-variant-ligatures: no-common-ligatures" class="">? =
</span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">nil</span><span style="font-variant-ligatures: no-common-ligatures" class="">) {</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span>
<span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">self</span><span style="font-variant-ligatures: no-common-ligatures" class="">.</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">species</span><span style="font-variant-ligatures: no-common-ligatures" class="">
= species</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo; min-height: 13px;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""></span><br class="">
</div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span>
<span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">if</span><span style="font-variant-ligatures: no-common-ligatures" class=""> level !=
</span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">nil</span><span style="font-variant-ligatures: no-common-ligatures" class=""> {</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span>
<span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">self</span><span style="font-variant-ligatures: no-common-ligatures" class="">.</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">level</span><span style="font-variant-ligatures: no-common-ligatures" class="">
= level!</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> }</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo; min-height: 13px;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""></span><br class="">
</div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span>
<span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">if</span><span style="font-variant-ligatures: no-common-ligatures" class=""> nickname !=
</span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">nil</span><span style="font-variant-ligatures: no-common-ligatures" class=""> {</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> </span>
<span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">self</span><span style="font-variant-ligatures: no-common-ligatures" class="">.</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">nickname</span><span style="font-variant-ligatures: no-common-ligatures" class="">
= nickname!</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> }</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""> }</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class="">}</span></div>
</div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-variant-ligatures: no-common-ligatures" class=""><br class="">
</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-family: Helvetica; font-size: 12px;" class="">In addition to be rather wordy, it arguably destroys the purpose of defining a default value for variable properties in the first place, since imho this approach is clearer (unless maybe for some
more complicated structs with multiple layers of initializer delegation):</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<span style="font-family: Helvetica; font-size: 12px;" class=""><br class="">
</span></div>
<div style="margin: 0px; font-size: 11px; line-height: normal; font-family: Menlo;" class="">
<div style="margin: 0px; line-height: normal;" class="">
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">struct</span><span style="font-variant-ligatures: no-common-ligatures" class=""> Pokemon {</span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">
</span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">let</span><span style="font-variant-ligatures: no-common-ligatures" class=""> species:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Species</span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">
</span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">var</span><span style="font-variant-ligatures: no-common-ligatures" class=""> level:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Int</span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">
</span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">var</span><span style="font-variant-ligatures: no-common-ligatures" class=""> nickname:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">String</span></div>
<div style="margin: 0px; line-height: normal; min-height: 13px;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""></span><br class="">
</div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">
</span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">init</span><span style="font-variant-ligatures: no-common-ligatures" class="">(species:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Species</span><span style="font-variant-ligatures: no-common-ligatures" class="">, level:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">Int</span><span style="font-variant-ligatures: no-common-ligatures" class=""> = 1, nickname:
</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">String</span><span style="font-variant-ligatures: no-common-ligatures" class=""> =
</span><span style="font-variant-ligatures: no-common-ligatures; color: #b4261a" class="">"bulby"</span><span style="font-variant-ligatures: no-common-ligatures" class="">) {</span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">
</span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">self</span><span style="font-variant-ligatures: no-common-ligatures" class="">.</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">species</span><span style="font-variant-ligatures: no-common-ligatures" class="">
= species</span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">
</span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">self</span><span style="font-variant-ligatures: no-common-ligatures" class="">.</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">level</span><span style="font-variant-ligatures: no-common-ligatures" class="">
= level</span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">
</span><span style="font-variant-ligatures: no-common-ligatures; color: #0433ff" class="">self</span><span style="font-variant-ligatures: no-common-ligatures" class="">.</span><span style="font-variant-ligatures: no-common-ligatures; color: #3495af" class="">nickname</span><span style="font-variant-ligatures: no-common-ligatures" class="">
= nickname</span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""> }</span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class="">}</span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""><br class="">
</span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""><span style="font-family: Helvetica; font-size: 12px;" class="">Thanks.</span></span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""><span style="font-family: Helvetica; font-size: 12px;" class=""><br class="">
</span></span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""><span style="font-family: Helvetica; font-size: 12px;" class="">Dimitri Racordon</span></span></div>
<div style="margin: 0px; line-height: normal;" class=""><span style="font-variant-ligatures: no-common-ligatures" class=""><span style="font-family: Helvetica; font-size: 12px;" class=""><br class="">
</span></span></div>
</div>
</div>
</div>
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