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.send { color:#77bb77; }
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.error { color:#AA0000; }</style></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div class="bloop_markdown"><p>Really? I must have overlooked that some pitched that design. </p>
<p>Okay now that I think through this whole scenario, I like the underscore iff there is a good name that will be present in the final version.</p>
<p>When Swift 3 drops, I’ll write a proposal for nested protocols which will refine your design (the original author went missing after pitching this idea, and Joe Groff told me that this probably out of scope for Swift 3)!</p>
<p>Your current design might become this in Swift 3.X and all protocols marked with an underscore will disappear:</p>
<pre><code class="swift">public /* closed */ enum Syntax {
public protocol NilLiteral { ... }
public protocol BooleanLiteral { ... }
public protocol IntegerLiteral { ... }
public protocol FloatLiteral { ... }
public protocol UnicodeScalarLiteral { ... }
public protocol ExtendedGraphemeClusterLiteral { ... }
public protocol StringLiteralLiteral { ... }
public protocol StringInterplolationLiteral { ... }
public protocol ArrayrLiteral { ... }
public protocol DictionaryLiteral { ... }
}
</code></pre>
<p></p></div><div class="bloop_original_html"><style>body{font-family:Helvetica,Arial;font-size:13px}</style><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> <br> <div id="bloop_sign_1466782073435774208" 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 24. Juni 2016 um 17:25:45, Matthew Johnson (<a href="mailto:matthew@anandabits.com">matthew@anandabits.com</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>
<div class="">The design in this proposal comes from the standard
library team. The intent is for the use of underscore here to
be consistent with other uses of underscore prefix in the standard
library. I’m not sure why you think this is different than
the rest...</div>
<div class=""><br class=""></div>
<br class="">
<div>
<blockquote type="cite" class="">
<div class="">On Jun 24, 2016, at 10:22 AM, Adrian Zubarev 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="">
<div class="bloop_markdown" style="font-family: Helvetica, Arial; font-size: 13px; 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; background-color: rgb(254, 254, 254);">
<p style="margin: 15px 0px; -webkit-margin-before: 0px;" class="">
I’m aware of that fact, but all types with underscore even in the
stdlib telling me to keep my hands of them, because something might
happen to them.</p>
<div class="">As an example we have <code class="" style="font-size: 10pt; font-family: Menlo, Consolas, 'Liberation Mono', Courier, monospace; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; background-color: rgb(248, 248, 248); color: inherit; border: 1px solid rgb(234, 234, 234); margin: 0px 2px; padding: 0px 5px; word-break: normal; word-wrap: normal; -webkit-margin-before: 0px;">_Strideable</code> protocol
which is visible by its name, but its declaration isn’t visible at
all:</div>
</div>
</div>
</blockquote>
<blockquote type="cite" class="">
<div class="bloop_markdown" style="font-family: Helvetica, Arial; font-size: 13px; 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; background-color: rgb(254, 254, 254);">
<pre style="margin: 15px 0px; font-family: Menlo, Consolas, 'Liberation Mono', Courier, monospace; font-size: 10pt; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; background-color: rgb(248, 248, 248); color: inherit; border: 1px solid rgb(204, 204, 204); overflow: auto; padding: 4px 8px; word-break: normal; word-wrap: normal;" class=""><code style="font-family: Menlo, Consolas, 'Liberation Mono', Courier, monospace; font-size: 10pt; border-top-left-radius: 3px; border-top-right-radius: 3px; border-bottom-right-radius: 3px; border-bottom-left-radius: 3px; background-color: rgb(248, 248, 248); color: inherit; border: 0px; margin: 0px; padding: 0px; word-break: normal; word-wrap: normal; -webkit-margin-before: 0px;" class="">// FIXME(ABI)(compiler limitation): Remove `_Strideable`.
// WORKAROUND <a href="rdar://25214598" style="color: rgb(65, 131, 196); background-color: inherit; text-decoration: none; -webkit-margin-before: 0px;" class="">rdar://25214598</a> - should be:
// protocol Strideable : Comparable {...}
% for Self in ['_Strideable', 'Strideable']:
</code></pre>
<p style="margin: 15px 0px;" class="">From<span class="Apple-converted-space"> </span><a href="https://github.com/apple/swift/blob/63c36dff0a327874a5041d46335bde314bc108d8/stdlib/public/core/Stride.swift.gyb" style="color: rgb(65, 131, 196); background-color: inherit; text-decoration: none; -webkit-margin-before: 0px;" class="">Stride.swift.gyb</a></p>
<div style="margin: 15px 0px;" class=""><br class="webkit-block-placeholder"></div>
</div>
<div class="bloop_original_html" style="font-family: Helvetica, Arial; font-size: 13px; 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; background-color: rgb(254, 254, 254);">
<div id="bloop_customfont" style="font-family: Helvetica, Arial; font-size: 13px; margin: 0px;" class=""><br class=""></div>
<br class="">
<div id="bloop_sign_1466781052554189056" class="bloop_sign">
<div style="font-family: helvetica, arial; font-size: 13px;" class="">-- <br class="">
Adrian Zubarev<br class="">
Sent with Airmail</div>
</div>
<br class="">
<p class="airmail_on" style="margin: 15px 0px;">Am 24. Juni 2016 um
17:09:53, Matthew Johnson (<a href="mailto:matthew@anandabits.com" style="color: rgb(65, 131, 196); background-color: inherit; text-decoration: none;" class="">matthew@anandabits.com</a>) schrieb:</p>
<blockquote type="cite" class="clean_bq" style="margin: 15px 0px;">
<div class=""><span style="margin-top: 0px; margin-bottom: 0px;" class=""><span style="font-family: 'helvetica Neue', helvetica; font-size: 14px; 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; background-color: rgb(255, 255, 255); float: none; display: inline !important;" class="">The underscore is used in the same way it is used
elsewhere in the standard library. The protocols must be
public because they need to be visible to user code in order for
the design to work correctly. However, they are considered
implementation details that users really shouldn’t know about.
This pattern is well established in the standard
library.</span></span></div>
</blockquote>
</div>
<div class="bloop_markdown" style="font-family: Helvetica, Arial; font-size: 13px; 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; background-color: rgb(254, 254, 254);">
<div style="margin: 15px 0px; -webkit-margin-before: 0px;" class=""><br class="webkit-block-placeholder"></div>
</div>
<span style="font-family: Helvetica, Arial; font-size: 13px; 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; background-color: rgb(254, 254, 254); float: none; display: inline !important;" class="">_______________________________________________</span><br style="font-family: Helvetica, Arial; font-size: 13px; 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; background-color: rgb(254, 254, 254);" class="">
<span style="font-family: Helvetica, Arial; font-size: 13px; 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; background-color: rgb(254, 254, 254); 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-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; background-color: rgb(254, 254, 254);" class="">
<a href="mailto:swift-evolution@swift.org" style="color: rgb(65, 131, 196); background-color: rgb(254, 254, 254); text-decoration: none; font-family: Helvetica, Arial; font-size: 13px; 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;" class="">swift-evolution@swift.org</a><br style="font-family: Helvetica, Arial; font-size: 13px; 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; background-color: rgb(254, 254, 254);" class="">
<a href="https://lists.swift.org/mailman/listinfo/swift-evolution" style="color: rgb(65, 131, 196); background-color: rgb(254, 254, 254); text-decoration: none; font-family: Helvetica, Arial; font-size: 13px; 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;" class="">https://lists.swift.org/mailman/listinfo/swift-evolution</a><br style="font-family: Helvetica, Arial; font-size: 13px; 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; background-color: rgb(254, 254, 254);" class=""></blockquote>
</div>
<br class="">
</div></div></span></blockquote></div><div class="bloop_markdown"><p></p></div></body></html>