<html><head><style>body{font-family:Helvetica,Arial;font-size:13px}</style></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;">+1 You are right Félix, it was only my own project that tempted me to return from each catch scope. </div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;"><br></div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;">But wouldn’t this confuse everyone?</div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;"><br></div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;">Here is an example:</div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;"><br></div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;"><b>do let/var newInstance = try throwingFuncReturns() catch {</b></div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;"><b><span class="Apple-tab-span" style="white-space:pre"> </span>// can not fall through at all</b></div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;"><b>}</b></div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;"><br></div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;">There is no chance the compile can guarantee that `<b>newInstance</b>` was assigned with a value, except if `newInstance` is an optional type, so this code may not fall through like the '<b>guard</b>‘ mechanism.</div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;"><br></div><div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;"><b>let newInstance: Type</b></div><div id="bloop_customfont" style="margin: 0px;"><div id="bloop_customfont" style="color: rgb(0, 0, 0); font-family: Helvetica, Arial; font-size: 13px; margin: 0px;"><b>do newInstance = try throwingFuncReturns() catch {</b></div><div id="bloop_customfont" style="margin: 0px;"><b><span class="Apple-tab-span" style="color: rgb(0, 0, 0); font-family: Helvetica, Arial; font-size: 13px; white-space: pre;"> </span>// if not returned from here or the newInstance is not set here the compiler should raise an error</b></div><div id="bloop_customfont" style="color: rgb(0, 0, 0); font-family: Helvetica, Arial; font-size: 13px; margin: 0px;"><b>}</b></div><div id="bloop_customfont" style="color: rgb(0, 0, 0); font-family: Helvetica, Arial; font-size: 13px; margin: 0px;"><br></div><div id="bloop_customfont" style="color: rgb(0, 0, 0); font-family: Helvetica, Arial; font-size: 13px; margin: 0px;">`<b>newInstance</b>` is only safe when throwing function returns without any errors or the instance was set inside the catch scope. This mimics the `if else` behavior. This can already be done with the existing `<b>do try catch</b>` mechanism.</div><div id="bloop_customfont" style="color: rgb(0, 0, 0); font-family: Helvetica, Arial; font-size: 13px; margin: 0px;"><br></div><div id="bloop_customfont" style="color: rgb(0, 0, 0); font-family: Helvetica, Arial; font-size: 13px; margin: 0px;"><div id="bloop_customfont" style="margin: 0px;"><b>let x: SomeThing</b></div><div id="bloop_customfont" style="margin: 0px;"><b>if condition {</b></div><div id="bloop_customfont" style="margin: 0px;"><b><span class="Apple-tab-span" style="white-space:pre"> </span>x = foo()</b></div><div id="bloop_customfont" style="margin: 0px;"><b>} else {</b></div><div id="bloop_customfont" style="margin: 0px;"><b><span class="Apple-tab-span" style="white-space:pre"> </span>x = bar()</b></div><div id="bloop_customfont" style="margin: 0px;"><b>}</b></div><div id="bloop_customfont" style="margin: 0px;"><b>use(x)</b></div><div id="bloop_customfont" style="margin: 0px;"><br></div><div id="bloop_customfont" style="margin: 0px;"><div id="bloop_customfont" style="margin: 0px;"><b>do try throwingFunc() catch {</b></div><div id="bloop_customfont" style="margin: 0px;"><b><span class="Apple-tab-span" style="white-space: pre;"> </span>// can fall through if needed (this means I can ignore the error or return/break)</b></div><div id="bloop_customfont" style="margin: 0px;"><b>}</b></div><div id="bloop_customfont" style="margin: 0px;"><b><br></b></div><div id="bloop_customfont" style="margin: 0px;">Another way do this right now would look like this:</div><div id="bloop_customfont" style="margin: 0px;"><br></div><div id="bloop_customfont" style="margin: 0px;"><div id="bloop_customfont" style="margin: 0px;"><b>do {</b></div><div id="bloop_customfont" style="margin: 0px;"><b><span class="Apple-tab-span" style="white-space:pre"> </span>try throwingFunc() </b></div><div id="bloop_customfont" style="margin: 0px;"><b>} catch _ { </b><b>} // will ignore the error</b></div><div id="bloop_customfont" style="margin: 0px;"><b><br></b></div><div id="bloop_customfont" style="margin: 0px;">As you can see only the first example can not fall though after catching the error, so wouldn’t it be better to support both syntax variants?</div><div id="bloop_customfont" style="margin: 0px;"><b><br></b></div><div id="bloop_customfont" style="margin: 0px;"><b>guard let/var newInstance = try throwingFuncReturns() catch {</b></div><div id="bloop_customfont" style="margin: 0px;"><div id="bloop_customfont" style="margin: 0px;"><b><span class="Apple-tab-span" style="white-space: pre;"> </span>// can not fall through</b></div><div id="bloop_customfont" style="margin: 0px;"><b>}</b></div><div><br></div><div><div id="bloop_customfont" style="margin: 0px;"><div id="bloop_customfont" style="margin: 0px;"><b>let newInstance: Type</b></div><div id="bloop_customfont" style="margin: 0px;"><div id="bloop_customfont" style="margin: 0px;"><b>do newInstance = try throwingFuncReturns() catch {</b></div><div id="bloop_customfont" style="margin: 0px;"><b><span class="Apple-tab-span" style="white-space: pre;"> </span>// if not returned from here or the newInstance is not set here the compiler should raise an error</b></div><div id="bloop_customfont" style="margin: 0px;"><b>}</b></div><div><b><br></b></div><div><div id="bloop_customfont" style="margin: 0px;"><b>do try throwingFunc() catch {</b></div><div id="bloop_customfont" style="margin: 0px;"><b><span class="Apple-tab-span" style="white-space: pre;"> </span>// can fall through if needed (this means I can ignore the error)</b></div><div id="bloop_customfont" style="margin: 0px;"><b>}</b></div></div></div></div></div></div></div></div></div></div> <br> <div id="bloop_sign_1454697774120125952" class="bloop_sign"><div style="font-family:helvetica,arial;font-size:13px">-- <br>Adrian Zubarev<br>Sent with Airmail</div></div> <br><p class="airmail_on">Am 5. Februar 2016 bei 19:40:46, Félix Cloutier (<a href="mailto:felixcca@yahoo.ca">felixcca@yahoo.ca</a>) schrieb:</p> <blockquote type="cite" class="clean_bq"><span><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div></div><div>
<title></title>
Unless you're declaring a variable with a single-statement try,
there's no reason to disallow fallthrough.<br class="">
<div class=""><br class="Apple-interchange-newline">
<span style="color: rgb(0, 0, 0); font-family: 'Lucida Grande'; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; display: inline !important; float: none;" class="">Félix</span></div>
<br class="">
<div>
<blockquote type="cite" class="">
<div class="">Le 5 févr. 2016 à 13:28:58, Adrian Zubarev via
swift-evolution <<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a>> a écrit :</div>
<br class="Apple-interchange-newline">
<div class="">
<div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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; margin: 0px;" class="">Right now the error handling mechanism will fall through
even if the error was handled inside the catch scope.</div>
<div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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; margin: 0px;" class="">
<div style="font-family: 'Source Code Pro'; font-size: 11px; margin: 0px; line-height: normal;" class=""><br class=""></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">enum Error: ErrorType
{</b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">case SomeError</b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">}</b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class=""><br class=""></b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">func throwingFunc() throws
{</b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">throw
Error.SomeError</b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">}</b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class=""><br class=""></b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">func throwingFuncReturns() throws
-> Int {</b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">return 0</b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">}</b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class=""><br class=""></b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">do { try throwingFunc() } catch
{</b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">/* do nothing */</b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">}</b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class=""><br class=""></b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">var num: Int</b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">do { num = try
throwingFuncReturns() } catch {</b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">/* do nothing */</b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">}</b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class=""><br class=""></b></font></div>
<div style="margin: 0px; line-height: normal;" class=""><font face="Helvetica" class=""><b class="">print("both fell
through")</b></font></div>
<div style="font-family: Helvetica, Arial; font-size: 13px;" class=""><br class=""></div>
</div>
<div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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; margin: 0px;" class="">To guarantee the safety of the execution from my point of
view the catch body may not fall through (for single try
statements), at least not by default.</div>
<div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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; margin: 0px;" class=""><br class=""></div>
<div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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; margin: 0px;" class="">I think it is fine to rename the proposed mechanism.</div>
<div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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; margin: 0px;" class=""><br class=""></div>
<div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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; margin: 0px;" class="">
<div class=""><b class="">do try throwingFunc() catch
{ </b></div>
<div class=""><b class="">/* handle error */ </b></div>
<div class=""><b class="">}</b></div>
<div class=""><b class=""><br class=""></b></div>
<div class=""><b class="">do try throwingFunc() catch _
{ </b></div>
<div class=""><b class="">/* handle error */ </b></div>
<div class=""><b class="">}</b></div>
<div class=""><b class=""><br class=""></b></div>
<div class=""><b class="">do try throwingFunc() catch pattern
{ </b></div>
<div class=""><b class="">/* handle error */ </b></div>
<div class=""><b class="">}</b></div>
<div class=""><b class=""><br class=""></b></div>
<div class=""><b class="">do try throwingFunc() catch pattern
{ </b></div>
<div class=""><b class="">/* handle error */ </b></div>
<div class=""><b class="">}</b></div>
<div class=""><b class=""><br class=""></b></div>
<div class=""><b class="">do let newInstance = try
throwingFuncReturns() catch </b><b class="">catch
pattern </b><b class="">where condition</b><b class=""> { </b></div>
<div class=""><b class="">/* handle error */ </b></div>
<div class=""><b class="">}</b></div>
<div class=""><br class=""></div>
<div class=""><b class="">do var newMutableInstance = try
throwingFuncReturns() catch pattern </b><b class="">where
condition</b><b class=""> { </b></div>
<div class=""><b class="">/* handle error */ </b></div>
<div class=""><b class="">}</b></div>
<div class=""><b class=""><br class=""></b></div>
<div class="">
<div class="">'<b class="">Where</b>' clause is significant for
catching wider range of errors that might occur.</div>
</div>
</div>
<br style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;" class="">
<div id="bloop_sign_1454695983058411008" class="bloop_sign" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<div style="font-family: helvetica, arial; font-size: 13px;" class="">-- <br class="">
Adrian Zubarev<br class="">
Sent with Airmail</div>
</div>
<br style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;" class="">
<p class="airmail_on" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
Am 5. Februar 2016 bei 19:05:12, Félix Cloutier (<a href="mailto:felixcca@yahoo.ca" class="">felixcca@yahoo.ca</a>)
schrieb:</p>
<blockquote type="cite" class="clean_bq" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<div class="" style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">
<div class=""></div>
<div class=""><span class="">We could do it without a new guard
syntax if `do` didn't need a block statement.<br class=""></span>
<div class=""><span class=""><br class="Apple-interchange-newline">
<span class="" style="font-family: 'Lucida Grande'; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; float: none; display: inline !important;">
Félix</span></span></div>
<br class="">
<div class="">
<blockquote type="cite" class="">
<div class="">Le 5 févr. 2016 à 12:54:47, Adrian Zubarev via
swift-evolution <<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a>> a écrit :</div>
<br class="Apple-interchange-newline">
<div class="">
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
Hello dear Swift community,</div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
this proposal might seem like some new syntax sugar, but it also
aims to escape the '<b class="">do { }</b>' scope from the
'<b class="">do try catch</b>‘ mechanism while making the existing
error handling more powerful.</div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
Lets assume we have some sort of network type, which can throw a
ton of different errors:</div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">struct TCPListener {</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
</div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">init(address: String) throws { /* implement */
}</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class=""><br class=""></b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">func accept() throws -> TCPConn { /* implement */
}</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class=""><br class=""></b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">/* ... */</b></div>
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<b class="">}</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
A way of implimentation might look like this:</div>
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<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">let listener: TCPListener</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">do {</b></div>
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<b class="">listener = try TCPListener("some valid
address")</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class=""><br class=""></b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">// we could do more work here, but if we need to catch
more</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">// errors we will result in a new PYRAMIDE OF
DOOM</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">} catch {</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">fatalError()</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">}</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
At this point think about the comment inside the '<b class="">do {
}</b>' scope. Such an application might result in a new pyramide of
doom as we know from optional unwrapping before '<b class="">guard
else</b>' mechanism was introduced.</div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">let clientConn: TCPConn</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">do {</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">clientConn = try listener.accept() // save to call
accept method</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">} catch {</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">fatalError()</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">} </b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
As you can see this application might not need the extra 'do' scope
at all, and if it does, the 'do try catch' is still there.</div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
I propose a new<span class="Apple-converted-space"> </span><b class="">error handling
mechanism</b><span class="Apple-converted-space"> </span>that
mimics the solution for optional pyramide of doom, which adds a
slightly better syntax and removes the unneeded/unused '<b class="">do { }</b>' scope (as for the example from above). Not only can
this mechanism guarantee the execution of a throwing function
without any errors (like a true guard condition) it also can assign
returned values to a new constant/variable.</div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
Introducing the '<b class="">guard try catch</b>' mechanism:</div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">guard try throwingFunc() catch { </b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">/* handle error */ </b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">}</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class=""><br class=""></b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">guard try throwingFunc() catch _ { </b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">/* handle error */ </b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">}</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class=""><br class=""></b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">guard try throwingFunc() catch pattern
{ </b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">/* handle error */ </b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">}</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class=""><br class=""></b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">guard try throwingFunc() catch pattern where condition
{ </b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">/* handle error */ </b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">}</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class=""><br class=""></b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">guard let newInstance = try throwingFuncReturns() catch
... { </b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">/* handle error */ </b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">}</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
Where '<b class="">...</b>' represents the different combinations
of possible patterns already showed in the first 4 examples.</div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
We also might want the return type to be mutable.</div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">guard var newMutableInstance = try
throwingFuncReturns() catch ... { </b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">/* handle error */ </b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">}</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
This mechanism also makes the error handling more powerful, since
it can catch more specific errors defined with '<b class="">where
condition</b>'.</div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
Lets rebuild the example from above with the new mechanism:</div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<br class=""></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">guard let listener = try TCPListener("some valid
address") catch {</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">fatalError()</b></div>
<div class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<b class="">}</b></div>
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<b class=""><br class=""></b></div>
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<b class="">guard let clientConn = try listener.accept() catch
{</b></div>
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<b class="">fatalError()</b></div>
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<b class="">} </b></div>
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One think that should be mentioned here is that the method call
from the second '<b class="">guard</b>' is safe, because a
'<b class="">guard</b>' body may not fall through.</div>
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Impact on existing codebase:<span class="Apple-converted-space"> </span><i class=""><u class="">None</u></i>, because the mechanism is new and does not break
any existing code.</div>
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<br class=""></div>
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I'm really curious about your opinions.</div>
<span class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">_______________________________________________</span><br class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
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swift-evolution mailing list</span><br class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<a href="mailto:swift-evolution@swift.org" class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
swift-evolution@swift.org</a><br class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
<a href="https://lists.swift.org/mailman/listinfo/swift-evolution" class="" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;">
https://lists.swift.org/mailman/listinfo/swift-evolution</a></div>
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</blockquote>
<span style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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="">_______________________________________________</span><br style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;" class="">
<span style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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="">swift-evolution mailing list</span><br style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;" class="">
<a href="mailto:swift-evolution@swift.org" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;" class="">swift-evolution@swift.org</a><br style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;" class="">
<a href="https://lists.swift.org/mailman/listinfo/swift-evolution" style="font-family: Helvetica, Arial; font-size: 13px; font-style: normal; font-variant: 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;" class="">https://lists.swift.org/mailman/listinfo/swift-evolution</a></div>
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