<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=""><br class=""><div><blockquote type="cite" class=""><div class="">On Jun 15, 2016, at 2:25 PM, 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="">How about this, it might make more sense and relax the behavior a little:</p><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 class="swift" 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;">// 1. file scope (Level 0)
// Level 0 because its declared at file scope
private struct A {
/* implicit private */ init() {} // Level 1
}
// Level 0
struct B {
// `A` is visible here and is seen as `fileprivate` because it is accessed
// from a level >= itself (imagine something like a "scope level tree").
// also every member of `A` are interpreted as
// `fileprivate` and everyting is visible again as intended
var a: A = A()
}
// 2. file scope (Level 0)
struct C {
// `A` is not visible here
// `B` is visible because its `internal` by default
}
</code></pre><p style="margin: 15px 0px;" class="">Does this makes sense to you?</p><div class=""><br class=""></div></div></div></blockquote><div><br class=""></div><div>This does not make sense to me at all. In order for this to be consistent with the rest of our access control rules `init` in #1 has the same visibility as `A`. That is why it is visible inside `B`. </div><div><br class=""></div><div>Your example #2 is just incorrect. `A` is visible inside the scope of `C`.</div><div><br class=""></div><div>Now that we have introduced a scope-dependent access modifier it is an incorrect mental model to consider members with no access modifier as having the exact same access modifier as the containing scope. This is no longer correct. They have the same *visibility*, not the same *access modifier*.</div><br class=""><blockquote type="cite" class=""><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);"><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=""> ___________
| file Root |
|___________|
|______________________
__|_________________ __|_________________________
| struct B (Level 0) | | private struct A (Level 0) |
|____________________| |____________________________|
| |
__|______________ _____|____________________
| var a (Level 1) | | private init() (Level 1) |
|_________________| |__________________________|
To check if `a` has visibility to `init` of `A` we need to compare the
visibility level of `B` against `A`. If it is equal than `private` is
handled as `fileprivate` which means that any other member from within
the scope of `A` are also handled as `fileprivate`. We've get the same result
if `B`s level is greater than `A`s. That means that we'll get back the
visibility by relaxing `private` in some cases as `fileprivate`.
</code></pre><p style="margin: 15px 0px;" class="">The described behavior is the same for<span class="Apple-converted-space"> </span><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: 1px solid rgb(234, 234, 234); margin: 0px 2px; padding: 0px 5px; word-break: normal; word-wrap: normal; -webkit-margin-before: 0px;" class="">private</code><span class="Apple-converted-space"> </span>on higher levels, but we don’t describe it as<span class="Apple-converted-space"> </span><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: 1px solid rgb(234, 234, 234); margin: 0px 2px; padding: 0px 5px; word-break: normal; word-wrap: normal;" class="">fileprivate</code><span class="Apple-converted-space"> </span>there (or can we do that?):</p><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 class="swift" 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;">extension B {
private func foo() {
// `boo` should be visible here
}
private func boo() {
// `foo` should be visible here
}
}
</code></pre><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_1466016831283463936" 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 15. Juni 2016 um 20:53:21, Robert Widmann via swift-evolution (<a href="mailto:swift-evolution@swift.org" style="color: rgb(65, 131, 196); background-color: inherit; text-decoration: none;" class="">swift-evolution@swift.org</a>) schrieb:</p><blockquote type="cite" class="clean_bq" style="margin: 15px 0px;"><span style="margin-top: 0px; margin-bottom: 0px;" class=""><div class=""><div class=""></div><div class="">Then it is no different from fileprivate.<br class=""><br class="">~Robert Widmann<br class=""><br class="">2016/06/15 11:47、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>> のメッセージ:<br class=""><br class="">><span class="Apple-converted-space"> </span><br class="">>> On Jun 15, 2016, at 1:37 PM, Robert Widmann <<a href="mailto:devteam.codafi@gmail.com" class="">devteam.codafi@gmail.com</a>> wrote:<br class="">>><span class="Apple-converted-space"> </span><br class="">>> The scope of the *declaration* is not the issue. The scope of its *members* is.<br class="">><span class="Apple-converted-space"> </span><br class="">> Let’s consider an example:<br class="">><span class="Apple-converted-space"> </span><br class="">> private struct Foo {<br class="">> var bar: Int<br class="">> }<br class="">><span class="Apple-converted-space"> </span><br class="">> // elsewhere in the same file:<br class="">> var foo = Foo(bar: 42)<br class="">> foo.bar = 44<br class="">><span class="Apple-converted-space"> </span><br class="">> `Foo` is declared private. Private for this declaration is at the file scope. The `bar` member has no access modifier so it has the same visibility as the struct itself, which is file scope. This will also be true of the implicitly synthesized memberwise initializer.<span class="Apple-converted-space"> </span><span class="Apple-converted-space"> </span><br class="">><span class="Apple-converted-space"> </span><br class="">> This means that it is possible to initialize `foo` with a newly constructed instance of `Foo` and to modify the `bar` member anywhere else in the same file.<br class="">><span class="Apple-converted-space"> </span><br class="">> If `bar` was also declared `private` this would not be possible as its visibility would be restricted to the surrounding scope of the initial declaration of `Foo`. This means `Foo` would need to provide an explicit initializer or factory method with `fileprivate` visibility in order to be usable.<br class="">><span class="Apple-converted-space"> </span><br class="">> Members with no explicit access modifier should have the same *visibility* as their containing type (with a maximum implicit visibility of internal), not the same *modifier* as their containing type. The only case where there is a distinction is the new `private` visibility. Maybe that is what is causing the confusion?<br class="">><span class="Apple-converted-space"> </span><br class="">> Does this help?<br class="">><span class="Apple-converted-space"> </span><br class="">> -Matthew<br class="">><span class="Apple-converted-space"> </span><br class="">>><span class="Apple-converted-space"> </span><br class="">>> ~Robert Widmann<br class="">>><span class="Apple-converted-space"> </span><br class="">>> 2016/06/15 11:36、Matthew Johnson <<a href="mailto:matthew@anandabits.com" class="">matthew@anandabits.com</a>> のメッセージ:<br class="">>><span class="Apple-converted-space"> </span><br class="">>>> The scope for a top-level declaration is the file itself. This means that top-level declarations with `private` and `fileprivate` should have the same behavior. They should not be uninstantiable or unusable.<br class="">>>><span class="Apple-converted-space"> </span><br class="">>>> -Matthew<br class="">>>><span class="Apple-converted-space"> </span><br class="">>>>> On Jun 15, 2016, at 1:31 PM, Robert Widmann via swift-evolution <<a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a>> wrote:<br class="">>>>><span class="Apple-converted-space"> </span><br class="">>>>> While implementing SE-0025 (fileprivate), I noticed an interesting bug in the proposal. Under the implementation outlined there, any top-level structure, class, or enum declared private cannot possibly be instantiated and so cannot be used in any way. Because of this, private top-level declarations are more often than not blown away entirely by the compiler for being unused. It seems strange to me to allow a key language feature to act solely as a hint to the optimizer to reduce the size of your binary. Perhaps the restrictions around private needs to be relaxed or the line between fileprivate and private needs to be investigated again by the community before inclusion in the language.<br class="">>>>><span class="Apple-converted-space"> </span><br class="">>>>> Thoughts?<br class="">>>>><span class="Apple-converted-space"> </span><br class="">>>>> ~Robert Widmann<br class="">>>>> _______________________________________________<br class="">>>>> swift-evolution mailing list<br class="">>>>> <a href="mailto:swift-evolution@swift.org" class="">swift-evolution@swift.org</a><br class="">>>>><span class="Apple-converted-space"> </span><a href="https://lists.swift.org/mailman/listinfo/swift-evolution" style="color: rgb(65, 131, 196); background-color: inherit; text-decoration: none;" class="">https://lists.swift.org/mailman/listinfo/swift-evolution</a><br class="">><span class="Apple-converted-space"> </span><br class="">_______________________________________________<br class="">swift-evolution mailing list<br class=""><a href="mailto:swift-evolution@swift.org" style="color: rgb(65, 131, 196); background-color: inherit; text-decoration: none;" class="">swift-evolution@swift.org</a><br class=""><a href="https://lists.swift.org/mailman/listinfo/swift-evolution" style="color: rgb(65, 131, 196); background-color: inherit; text-decoration: none;" class="">https://lists.swift.org/mailman/listinfo/swift-evolution</a><br class=""></div></div></span></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=""></div></blockquote></div><br class=""></body></html>