<html><head><style>
body {
font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
padding:1em;
margin:auto;
background:#fefefe;
}
h1, h2, h3, h4, h5, h6 {
font-weight: bold;
}
h1 {
color: #000000;
font-size: 28pt;
}
h2 {
border-bottom: 1px solid #CCCCCC;
color: #000000;
font-size: 24px;
}
h3 {
font-size: 18px;
}
h4 {
font-size: 16px;
}
h5 {
font-size: 14px;
}
h6 {
color: #777777;
background-color: inherit;
font-size: 14px;
}
hr {
height: 0.2em;
border: 0;
color: #CCCCCC;
background-color: #CCCCCC;
display: inherit;
}
p, blockquote, ul, ol, dl, li, table, pre {
margin: 15px 0;
}
a, a:visited {
color: #4183C4;
background-color: inherit;
text-decoration: none;
}
#message {
border-radius: 6px;
border: 1px solid #ccc;
display:block;
width:100%;
height:60px;
margin:6px 0px;
}
button, #ws {
font-size: 12 pt;
padding: 4px 6px;
border-radius: 5px;
border: 1px solid #bbb;
background-color: #eee;
}
code, pre, #ws, #message {
font-family: Monaco;
font-size: 10pt;
border-radius: 3px;
background-color: #F8F8F8;
color: inherit;
}
code {
border: 1px solid #EAEAEA;
margin: 0 2px;
padding: 0 5px;
}
pre {
border: 1px solid #CCCCCC;
overflow: auto;
padding: 4px 8px;
}
pre > code {
border: 0;
margin: 0;
padding: 0;
}
#ws { background-color: #f8f8f8; }
.bloop_markdown table {
border-collapse: collapse;
font-family: Helvetica, arial, freesans, clean, sans-serif;
color: rgb(51, 51, 51);
font-size: 15px; line-height: 25px;
padding: 0; }
.bloop_markdown table tr {
border-top: 1px solid #cccccc;
background-color: white;
margin: 0;
padding: 0; }
.bloop_markdown table tr:nth-child(2n) {
background-color: #f8f8f8; }
.bloop_markdown table tr th {
font-weight: bold;
border: 1px solid #cccccc;
margin: 0;
padding: 6px 13px; }
.bloop_markdown table tr td {
border: 1px solid #cccccc;
margin: 0;
padding: 6px 13px; }
.bloop_markdown table tr th :first-child, table tr td :first-child {
margin-top: 0; }
.bloop_markdown table tr th :last-child, table tr td :last-child {
margin-bottom: 0; }
.bloop_markdown blockquote{
border-left: 4px solid #dddddd;
padding: 0 15px;
color: #777777; }
blockquote > :first-child {
margin-top: 0; }
blockquote > :last-child {
margin-bottom: 0; }
code, pre, #ws, #message {
word-break: normal;
word-wrap: normal;
}
hr {
display: inherit;
}
.bloop_markdown :first-child {
-webkit-margin-before: 0;
}
code, pre, #ws, #message {
font-family: Menlo, Consolas, Liberation Mono, Courier, monospace;
}
.send { color:#77bb77; }
.server { color:#7799bb; }
.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>Currently I could implement the whole type like this:</p>
<pre><code class="swift">public struct Type<T> : Hashable, CustomStringConvertible, CustomDebugStringConvertible {
// Anyone knows a better name?
public let sealed: T.Type = T.self
public let hashValue: Int = ObjectIdentifier(T.self).hashValue
// Inspired by SE-0101
public static var size: Int { return sizeof(T.self) }
public static var stride: Int { return strideof(T.self) }
public static var alignment: Int { return alignof(T.self) }
public var size: Int { return Type<T>.size }
public var stride: Int { return Type<T>.stride }
public var alignment: Int { return Type<T>.alignment }
public var description: String { return "Type<\(self.sealed)>" }
public var debugDescription: String {
return "<" + self.description + " size: \(self.size) stride: \(self.stride) alignment: \(self.alignment)>"
}
}
public func ==<T, U>(lhs: Type<T>, rhs: Type<U>) -> Bool {
return lhs.hashValue == rhs.hashValue
}
</code></pre>
<p>I also added static computed properties to access the the memory layout without any initialization.</p>
<p><code>Type<Int>.size</code> reads really great to me.</p>
<p>I’m curious about the feedback from the Swift community. :)</p>
<p>PS: All my replies are markdown formatted. If anyone can’t read them, here is a formatted gist: <a href="https://gist.github.com/DevAndArtist/c35284ac12806c13eff302d1cf347ac8">https://gist.github.com/DevAndArtist/c35284ac12806c13eff302d1cf347ac8</a></p>
<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_1468060314057022976" 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 9. Juli 2016 um 12:03:39, Adrian Zubarev (<a href="mailto:adrian.zubarev@devandartist.com">adrian.zubarev@devandartist.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;"><div></div><div>
<title></title>
<div class="bloop_markdown">
<p>Correcting the function from the very first post:</p>
<pre><code class="swift">public func ==<T, U>(lhs: Type<T>, rhs: Type<U>) -> Bool {
return lhs.hashValue == rhs.hashValue
}
</code></pre></div>
<div class="bloop_original_html">
<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_1468058593060718080" 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 9. Juli 2016 um 11:55:00, Adrian Zubarev
(<a href="mailto:adrian.zubarev@devandartist.com">adrian.zubarev@devandartist.com</a>)
schrieb:</p>
<blockquote type="cite" class="clean_bq">
<div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">
<div>
<div class="bloop_markdown">
<p><span>Here are a few more thoughts on solving a few problems
with dropped <code>.self</code> in mind:</span></p>
<ol>
<li>
<p><span><code>Type<SomeType></code> cannot become
<code>Type<Type<SomeType>></code> to prevent infinite
recursion.</span></p>
</li>
<li>
<p><span>Any other type without the short form for initializer
<code>SomeType(...)</code> or explicit access to static members or
initializer like <code>SomeType.init(...)</code> or
<code>SomeType.staticMember</code> will be automatically become
<code>Type<SomeType></code> - if it’s not part of an array or
dictionary shorthand syntax.</span></p>
</li>
<li>
<p><span>For array and dictionary shorthand syntax any type (except
other nested array and dictionary shorthand types) does not follow
the second rule from above (dropped <code>.self</code> in
mind):</span></p>
<ul>
<li><span><code>[SomeType]()</code> equals
<code>Array<SomeType>()</code></span></li>
<li><span><code>[Type<SomeType>]()</code> equals
<code>Array<Type<SomeType>>()</code></span></li>
<li><span><code>[SomeKeyType: SomeValueType]()</code> equals
<code>Dictionary<SomeKeyType,
SomeValueType>()</code></span></li>
<li><span><code>[Type<SomeKeyType>:
Type<SomeValueType>]()</code> equals
<code>Dictionary<Type<SomeKeyType>,
Type<SomeValueType>>()</code></span></li>
</ul>
</li>
</ol>
<p><span>We also could extend <code>Type<T></code> to provide
more useful informations:</span></p>
<pre><span><code class="swift">public struct Type<T> : Hashable, CustomStringConvertible, CustomDebugStringConvertible {
// Anyone knows a better name?
public let sealed: T.Type
public var hashValue: Int { /* implement */ }
// Inspired by SE-0101
public var size: Int { /* implement */ }
public var stride: Int { /* implement */ }
public var alignment: Int { /* implement */ }
public var description: String { /* implement */ }
public var debugDescription: String { /* implement */ }
public init() { /* implement */ }
}
</code></span></pre></div>
<div class="bloop_original_html">
<div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;">
<span><br></span></div>
<span><br></span>
<div id="bloop_sign_1468055291563095040" class="bloop_sign">
<div style="font-family:helvetica,arial;font-size:13px">
<span>-- <br>
Adrian Zubarev<br>
Sent with Airmail</span></div>
</div>
<span><br></span>
<p class="airmail_on"><span>Am 8. Juli 2016 um 22:06:30, Adrian
Zubarev (<a href="mailto:adrian.zubarev@devandartist.com">adrian.zubarev@devandartist.com</a>)
schrieb:</span></p>
<blockquote type="cite" class="clean_bq">
<div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;">
<div>
<div class="bloop_markdown">
<p><span><span>Hello Swift community, before Swift 3 drops I’d like
to discuss if it is reasonable to consider to create a standalone
type to drop/seal the <code>T.Type</code> magic?</span></span></p>
<p><span>However this change does not play well with the proposal
of dropping the <code>.self</code> compiler magic.</span></p>
<p><span>Some bikeshedding:</span></p>
<pre><span><code class="swift">public struct Type<T> : Hashable {
// Seal the `.Type` magic into this standalone type.
// Disallow `.Type` usage elsewhere
public let sealed: T.Type
public var hashValue: Int { /* implement somehow */ }
public init() {
// Or do it somehow different for the sake of dropping `.self` magic
self.sealed = T.self
}
}
public func ==<T>(lhs: Type<T>, rhs: Type<T>) -> Bool {
return lhs.hashValue == rhs.hashValue
}
</code></span></pre>
<p><span>Downside of this approach is the accessibility of the
<code>.Type</code> instance:</span></p>
<pre><span><code class="swift">protocol Initializable {
init()
}
func foo<T : Initializable>(type: Type<T>) -> T {
// It would be nice if we could use `type.init()` instead, but than we
// would need more compiler magic :/
return type.sealed.init()
}
</code></span></pre>
<p><span>I couldn’t come up with a better name than
<code>sealed</code>, if anyone has a better idea feel free to share
your thoughts.</span></p>
<p><span>Remember this is a discussion and not (yet) a detailed
proposal, where everyone can provide feedback and bikeshedding for
a better design.</span></p>
</div>
<div class="bloop_original_html">
<div id="bloop_customfont" style="font-family:Helvetica,Arial;font-size:13px; color: rgba(0,0,0,1.0); margin: 0px; line-height: auto;">
<span><br></span></div>
<span><br></span>
<div id="bloop_sign_1468001575976519168" class="bloop_sign">
<div style="font-family:helvetica,arial;font-size:13px">
<span>-- <br>
Adrian Zubarev<br>
Sent with Airmail</span></div>
</div>
</div>
<div class="bloop_markdown"></div>
</div>
</div>
</blockquote>
</div>
<div class="bloop_markdown"></div>
</div>
</div>
</blockquote>
</div>
<div class="bloop_markdown"></div>
</div></div></span></blockquote></div><div class="bloop_markdown"><p></p></div></body></html>