# \[Accepted\] SE-0028 Modernizing Swift's Debugging Identifiers (\_\_LINE\_\_, etc) **URL:** \ **Category:** Announcements\ **Created:** [February 4, 2016, 12:39am UTC](https://forums.swift.org/t/accepted-se-0028-modernizing-swifts-debugging-identifiers-line-etc/1303 "2016-02-04T00:39:37Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![Chris\_Lattner](https://avatars.discourse-cdn.com/v4/letter/c/bc8723/32.png) [@Chris\_Lattner](https://forums.swift.org/u/Chris_Lattner)\ **Post date:** [February 4, 2016, 12:39am UTC](https://forums.swift.org/t/accepted-se-0028-modernizing-swifts-debugging-identifiers-line-etc/1303/1 "2016-02-04T00:39:37Z")
Proposal Link: [swift-evolution/0028-modernizing-debug-identifiers.md at master · apple/swift-evolution · GitHub](https://github.com/apple/swift-evolution/blob/master/proposals/0028-modernizing-debug-identifiers.md) The review of SE-0028 "Modernizing Swift's Debugging Identifiers" ran from January 29… February 2, 2016. The proposal has been \*accepted\*, with modifications: \* The core team agrees that we should rename all of the existing \_\_FILE\_\_, \_\_LINE\_\_, \_\_COLUMN\_\_, \_\_FUNCTION\_\_, and \_\_DSO\_HANDLE\_\_ symbols to lowercase equivalents in the # namespace: #file, #line, #column, #function, #dsohandle. This includes keeping \_\_FUNCTION\_\_, and making #line have the dual behavior of being a directive when it is the first token on a line, but an expression otherwise. Renaming these symbols improves uniformity within the Swift language, and keeping all of them provides a smooth transition path from the old syntax to the new syntax. \* The core team isn’t thrilled with the magic “first token on a line” whitespace behavior that #line will be getting, and would like someone to start a discussion about renaming the old #line directive to something more specific and tailored to its purpose. Once that name and syntax is settled, we can rename the directive and remove the whitespace rule. \* The core team requests that #symbol be split out into a separate proposal, because it needs more detailed design work, and is an additive feature. For example, it might be appealing to provide a "#mangledName” expression that provides the current symbol as a mangled name: when fed into a demangler, a more structured form of the current symbol would be available. Thank you to Erica Sadun for driving this forward! -Chris Lattner Review Manager ---
**Author:** ![Chris\_Lattner](https://avatars.discourse-cdn.com/v4/letter/c/bc8723/32.png) [@Chris\_Lattner](https://forums.swift.org/u/Chris_Lattner)\ **Post date:** [February 4, 2016, 12:48am UTC](https://forums.swift.org/t/accepted-se-0028-modernizing-swifts-debugging-identifiers-line-etc/1303/2 "2016-02-04T00:48:59Z")
To clarify, I meant keeping the behavior of \_\_FUNCTION\_\_, but renaming it to #function. -Chris > **···** > > > On Feb 3, 2016, at 4:39 PM, Chris Lattner \ wrote: > > > > Proposal Link: [https://github.com/apple/swift-evolution/blob/master/proposals/0028-modernizing-debug-identifiers.md](https://github.com/apple/swift-evolution/blob/master/proposals/0028-modernizing-debug-identifiers.md) > > > > The review of SE-0028 "Modernizing Swift's Debugging Identifiers" ran from January 29… February 2, 2016. The proposal has been \*accepted\*, with modifications: > > > > \* The core team agrees that we should rename all of the existing \_\_FILE\_\_, \_\_LINE\_\_, \_\_COLUMN\_\_, \_\_FUNCTION\_\_, and \_\_DSO\_HANDLE\_\_ symbols to lowercase equivalents in the # namespace: #file, #line, #column, #function, #dsohandle. This includes keeping \_\_FUNCTION\_\_, ---
**Author:** ![dabrahams](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/dabrahams/32/9815_2.png) [@dabrahams](https://forums.swift.org/u/dabrahams)\ **Post date:** [February 4, 2016, 8:24am UTC](https://forums.swift.org/t/accepted-se-0028-modernizing-swifts-debugging-identifiers-line-etc/1303/3 "2016-02-04T08:24:25Z")
> Proposal Link: > [https://github.com/apple/swift-evolution/blob/master/proposals/0028-modernizing-debug-identifiers.md](https://github.com/apple/swift-evolution/blob/master/proposals/0028-modernizing-debug-identifiers.md) > > The review of SE-0028 "Modernizing Swift's Debugging Identifiers" ran > from January 29… February 2, 2016. The proposal has been \*accepted\*, > with modifications: > > \* The core team agrees that we should rename all of the existing > \_\_FILE\_\_, \_\_LINE\_\_, \_\_COLUMN\_\_, \_\_FUNCTION\_\_, and \_\_DSO\_HANDLE\_\_ > symbols to lowercase equivalents in the # namespace: #file, #line, > #column, #function, #dsohandle. This includes keeping \_\_FUNCTION\_\_, > and making #line have the dual behavior of being a directive when it > is the first token on a line, but an expression otherwise. Renaming > these symbols improves uniformity within the Swift language, and > keeping all of them provides a smooth transition path from the old > syntax to the new syntax. > > \* The core team isn’t thrilled with the magic “first token on a line” > whitespace behavior that #line will be getting, and would like someone > to start a discussion about renaming the old #line directive to > something more specific and tailored to its purpose. Once that name > and syntax is settled, we can rename the directive and remove the > whitespace rule. I'm afraid we'll ultimately need to solve this some other way than by choosing a different name. We're eventually going to end up with something meaning #sourceLocation (modulo capitalization) and that's obviously (IMO) going to be the right name for both entities. > **···** > > on Wed Feb 03 2016, Chris Lattner \ wrote: > > > \* The core team requests that #symbol be split out into a separate > > proposal, because it needs more detailed design work, and is an > > additive feature. For example, it might be appealing to provide a > > "#mangledName” expression that provides the current symbol as a > > mangled name: when fed into a demangler, a more structured form of the > > current symbol would be available. > > > > Thank you to Erica Sadun for driving this forward! > > > > -Chris Lattner > > Review Manager > > \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ > > swift-evolution mailing list > > swift-evolution@swift.org > > [https://lists.swift.org/mailman/listinfo/swift-evolution](https://lists.swift.org/mailman/listinfo/swift-evolution) > > -- > -Dave ---
**Author:** ![Trent\_Nadeau](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/trent_nadeau/32/806_2.png) [@Trent\_Nadeau](https://forums.swift.org/u/Trent_Nadeau)\ **Post date:** [February 4, 2016, 1:23am UTC](https://forums.swift.org/t/accepted-se-0028-modernizing-swifts-debugging-identifiers-line-etc/1303/4 "2016-02-04T01:23:20Z")
Excellent. Consistency within the language makes it easier to remember, read, and teach. Congratulations, Erica! > **···** > > On Wed, Feb 3, 2016 at 7:48 PM, Chris Lattner via swift-evolution \< swift-evolution@swift.org\> wrote: > > > On Feb 3, 2016, at 4:39 PM, Chris Lattner \ wrote: > > > > Proposal Link: > > [https://github.com/apple/swift-evolution/blob/master/proposals/0028-modernizing-debug-identifiers.md](https://github.com/apple/swift-evolution/blob/master/proposals/0028-modernizing-debug-identifiers.md) > > > > The review of SE-0028 "\*Modernizing Swift's Debugging Identifiers\*" ran > > from January 29… February 2, 2016. The proposal has been \*\*accepted\*\*, > > with modifications: > > > > \* The core team agrees that we should rename all of the > > existing \_\_FILE\_\_, \_\_LINE\_\_, \_\_COLUMN\_\_, \_\_FUNCTION\_\_, and \_\_DSO\_HANDLE\_\_ > > symbols to lowercase equivalents in the # namespace: #file, #line, #column, > > #function, #dsohandle. This includes keeping \_\_FUNCTION\_\_, > > > > To clarify, I meant keeping the behavior of \_\_FUNCTION\_\_, but renaming it > > to #function. > > > > -Chris > > > > \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ > > swift-evolution mailing list > > swift-evolution@swift.org > > [https://lists.swift.org/mailman/listinfo/swift-evolution](https://lists.swift.org/mailman/listinfo/swift-evolution) > > -- > Trent Nadeau ---
**Author:** ![Erica\_Sadun](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/erica_sadun/32/243_2.png) [@Erica\_Sadun](https://forums.swift.org/u/Erica_Sadun)\ **Post date:** [February 4, 2016, 3:03pm UTC](https://forums.swift.org/t/accepted-se-0028-modernizing-swifts-debugging-identifiers-line-etc/1303/5 "2016-02-04T15:03:02Z")
On the "Renaming #line, the line control statement" thread, Brent Royal-Gordon suggests introducing a different grammar, specifically: #reset line=50, file="foo.swift" that could be applied to all the newly renamed items, not just #line. Is this feasible? -- Erica > **···** > > > On Feb 4, 2016, at 1:24 AM, Dave Abrahams via swift-evolution \ wrote: > > > > I'm afraid we'll ultimately need to solve this some other way than by > > choosing a different name. We're eventually going to end up with > > something meaning #sourceLocation (modulo capitalization) and that's > > obviously (IMO) going to be the right name for both entities. ---
**Author:** ![Erica\_Sadun](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/erica_sadun/32/243_2.png) [@Erica\_Sadun](https://forums.swift.org/u/Erica_Sadun)\ **Post date:** [February 4, 2016, 1:31am UTC](https://forums.swift.org/t/accepted-se-0028-modernizing-swifts-debugging-identifiers-line-etc/1303/6 "2016-02-04T01:31:33Z")
A few q's: \* #mangledname, I presume? To retain lowercase? \* Do you want #symbol (e.g. Swift.Dictionary.Foo(\_: Int, y: CustomType)) pushed now or saved for post 3.0? (Although SE-0021 is in 2.2?) \* Will #context/#releasecontext/#debugcontext be split out to a separate proposal or dropped entirely? And thank you all again, -- E > **···** > > > > On Feb 3, 2016, at 4:39 PM, Chris Lattner \\> wrote: > > > > > > Proposal Link: [https://github.com/apple/swift-evolution/blob/master/proposals/0028-modernizing-debug-identifiers.md](https://github.com/apple/swift-evolution/blob/master/proposals/0028-modernizing-debug-identifiers.md) > > > > > > The review of SE-0028 "Modernizing Swift's Debugging Identifiers" ran from January 29… February 2, 2016. The proposal has been \*accepted\*, with modifications: > > > > > > \* The core team agrees that we should rename all of the existing \_\_FILE\_\_, \_\_LINE\_\_, \_\_COLUMN\_\_, \_\_FUNCTION\_\_, and \_\_DSO\_HANDLE\_\_ symbols to lowercase equivalents in the # namespace: #file, #line, #column, #function, #dsohandle. This includes keeping \_\_FUNCTION\_\_, > > > > To clarify, I meant keeping the behavior of \_\_FUNCTION\_\_, but renaming it to #function. > > > > \* The core team requests that #symbol be split out into a separate proposal, because it needs more detailed design work, and is an additive feature. For example, it might be appealing to provide a "#mangledName” expression that provides the current symbol as a mangled name: when fed into a demangler, a more structured form of the current symbol would be available. ---
**Author:** ![James\_Hillhouse\_IV](https://avatars.discourse-cdn.com/v4/letter/j/58956e/32.png) [@James\_Hillhouse\_IV](https://forums.swift.org/u/James_Hillhouse_IV)\ **Post date:** [February 4, 2016, 2:28am UTC](https://forums.swift.org/t/accepted-se-0028-modernizing-swifts-debugging-identifiers-line-etc/1303/7 "2016-02-04T02:28:09Z")
+Inf to Erica for this. Jim jimhillhouse@me.com 512-484-9489 > **···** > > > On Feb 3, 2016, at 7:23 PM, Trent Nadeau via swift-evolution \ wrote: > > > > Excellent. Consistency within the language makes it easier to remember, read, and teach. > > > > Congratulations, Erica! > > > > > On Wed, Feb 3, 2016 at 7:48 PM, Chris Lattner via swift-evolution \ wrote: > > > > > > > On Feb 3, 2016, at 4:39 PM, Chris Lattner \ wrote: > > > > > > > > Proposal Link: [https://github.com/apple/swift-evolution/blob/master/proposals/0028-modernizing-debug-identifiers.md](https://github.com/apple/swift-evolution/blob/master/proposals/0028-modernizing-debug-identifiers.md) > > > > > > > > The review of SE-0028 "Modernizing Swift's Debugging Identifiers" ran from January 29… February 2, 2016. The proposal has been \*accepted\*, with modifications: > > > > > > > > \* The core team agrees that we should rename all of the existing \_\_FILE\_\_, \_\_LINE\_\_, \_\_COLUMN\_\_, \_\_FUNCTION\_\_, and \_\_DSO\_HANDLE\_\_ symbols to lowercase equivalents in the # namespace: #file, #line, #column, #function, #dsohandle. This includes keeping \_\_FUNCTION\_\_, > > > > > > To clarify, I meant keeping the behavior of \_\_FUNCTION\_\_, but renaming it to #function. > > > > > > -Chris > > > > > > \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ > > > swift-evolution mailing list > > > swift-evolution@swift.org > > > [https://lists.swift.org/mailman/listinfo/swift-evolution](https://lists.swift.org/mailman/listinfo/swift-evolution) > > > > -- > > Trent Nadeau > > \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ > > swift-evolution mailing list > > swift-evolution@swift.org > > [https://lists.swift.org/mailman/listinfo/swift-evolution](https://lists.swift.org/mailman/listinfo/swift-evolution) ---
**Author:** ![Chris\_Lattner](https://avatars.discourse-cdn.com/v4/letter/c/bc8723/32.png) [@Chris\_Lattner](https://forums.swift.org/u/Chris_Lattner)\ **Post date:** [February 4, 2016, 4:37am UTC](https://forums.swift.org/t/accepted-se-0028-modernizing-swifts-debugging-identifiers-line-etc/1303/8 "2016-02-04T04:37:55Z")
> > > Proposal Link: [https://github.com/apple/swift-evolution/blob/master/proposals/0028-modernizing-debug-identifiers.md](https://github.com/apple/swift-evolution/blob/master/proposals/0028-modernizing-debug-identifiers.md) > > > > > > The review of SE-0028 "Modernizing Swift's Debugging Identifiers" ran from January 29… February 2, 2016. The proposal has been \*accepted\*, with modifications: > > > > > > \* The core team agrees that we should rename all of the existing \_\_FILE\_\_, \_\_LINE\_\_, \_\_COLUMN\_\_, \_\_FUNCTION\_\_, and \_\_DSO\_HANDLE\_\_ symbols to lowercase equivalents in the # namespace: #file, #line, #column, #function, #dsohandle. This includes keeping \_\_FUNCTION\_\_, > > > > To clarify, I meant keeping the behavior of \_\_FUNCTION\_\_, but renaming it to #function. > > > > \* The core team requests that #symbol be split out into a separate proposal, because it needs more detailed design work, and is an additive feature. For example, it might be appealing to provide a "#mangledName” expression that provides the current symbol as a mangled name: when fed into a demangler, a more structured form of the current symbol would be available. > > A few q's: > > \* #mangledname, I presume? To retain lowercase? Yes, that would make sense. However, the demangler API’s aren’t currently very awesome for Swift, so this may be a theoretical goal. We should discuss whether this idea even makes sense. > \* Do you want #symbol (e.g. Swift.Dictionary.Foo(\_: Int, y: CustomType)) pushed now or saved for post 3.0? (Although SE-0021 is in 2.2?) It’s fine to discuss it now. Things that need to be figured out are things like: how specific to make this? In a getter, should it say the getter, or just the property? In a closure within a getter, should it somehow indicate the closure, or just the getter? etc. > \* Will #context/#releasecontext/#debugcontext be split out to a separate proposal or dropped entirely? I think they’d have to be separately motivated by a problem being solved, and being separate is good. -Chris > **···** > > > On Feb 3, 2016, at 5:31 PM, Erica Sadun \ wrote: > > > > > > On Feb 3, 2016, at 4:39 PM, Chris Lattner \\> wrote: ---
**Author:** ![Chris\_Lattner](https://avatars.discourse-cdn.com/v4/letter/c/bc8723/32.png) [@Chris\_Lattner](https://forums.swift.org/u/Chris_Lattner)\ **Post date:** [February 4, 2016, 5:29pm UTC](https://forums.swift.org/t/accepted-se-0028-modernizing-swifts-debugging-identifiers-line-etc/1303/9 "2016-02-04T17:29:28Z")
> > I'm afraid we'll ultimately need to solve this some other way than by > > choosing a different name. We're eventually going to end up with > > something meaning #sourceLocation (modulo capitalization) and that's > > obviously (IMO) going to be the right name for both entities. I don’t agree with you Dave, these are certainly related, but also very different operations. > On the "Renaming #line, the line control statement" thread, Brent Royal-Gordon suggests introducing a different grammar, > specifically: > > #reset line=50, file="foo.swift" > > that could be applied to all the newly renamed items, not just #line. Is this feasible? Yep, something with its own unique grammar would be fine, particularly for the directive form. I’ll comment in the other thread. -Chris > **···** > > > On Feb 4, 2016, at 7:03 AM, Erica Sadun via swift-evolution \ wrote: > > > > > On Feb 4, 2016, at 1:24 AM, Dave Abrahams via swift-evolution \\> wrote: ---
**Author:** ![dabrahams](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/dabrahams/32/9815_2.png) [@dabrahams](https://forums.swift.org/u/dabrahams)\ **Post date:** [February 4, 2016, 7:17pm UTC](https://forums.swift.org/t/accepted-se-0028-modernizing-swifts-debugging-identifiers-line-etc/1303/10 "2016-02-04T19:17:59Z")
> > > I'm afraid we'll ultimately need to solve this some other way than by > > > choosing a different name. We're eventually going to end up with > > > something meaning #sourceLocation (modulo capitalization) and that's > > > obviously (IMO) going to be the right name for both entities. > > I don’t agree with you Dave, these are certainly related, but also very different operations. They both represent source locations. I don't believe they need to have identical names, but they should at least both contain that phrase. I guess if there's a way to distinguish them while keeping the common language for the common concept, that makes renaming enough of a solution. So, I guess I'm agreeing with you. > **···** > > > On Feb 4, 2016, at 9:29 AM, Chris Lattner \ wrote: > > > > > On Feb 4, 2016, at 7:03 AM, Erica Sadun via swift-evolution \\> wrote: > > > > > > > On Feb 4, 2016, at 1:24 AM, Dave Abrahams via swift-evolution \\> wrote: > > > > On the "Renaming #line, the line control statement" thread, Brent Royal-Gordon suggests introducing a different grammar, > > > specifically: > > > > > > #reset line=50, file="foo.swift" > > > > > > that could be applied to all the newly renamed items, not just #line. Is this feasible? > > > > Yep, something with its own unique grammar would be fine, particularly for the directive form. I’ll comment in the other thread. > > > > -Chris ---
**Author:** ![Chris\_Lattner](https://avatars.discourse-cdn.com/v4/letter/c/bc8723/32.png) [@Chris\_Lattner](https://forums.swift.org/u/Chris_Lattner)\ **Post date:** [February 4, 2016, 10:38pm UTC](https://forums.swift.org/t/accepted-se-0028-modernizing-swifts-debugging-identifiers-line-etc/1303/11 "2016-02-04T22:38:44Z")
No, they don’t, at least not in the same way. The directive only contains the file and line. The expressions can produce the column and function. These are related, but different. -Chris > **···** > > > On Feb 4, 2016, at 11:17 AM, Dave Abrahams \ wrote: > > > > > On Feb 4, 2016, at 9:29 AM, Chris Lattner \\> wrote: > > > > > > > On Feb 4, 2016, at 7:03 AM, Erica Sadun via swift-evolution \\> wrote: > > > > > > > > > On Feb 4, 2016, at 1:24 AM, Dave Abrahams via swift-evolution \\> wrote: > > > > > > > > > > I'm afraid we'll ultimately need to solve this some other way than by > > > > > choosing a different name. We're eventually going to end up with > > > > > something meaning #sourceLocation (modulo capitalization) and that's > > > > > obviously (IMO) going to be the right name for both entities. > > > > > > I don’t agree with you Dave, these are certainly related, but also very different operations. > > > > They both represent source locations. ---
**Author:** ![dabrahams](https://sea2.discourse-cdn.com/swift/user_avatar/forums.swift.org/dabrahams/32/9815_2.png) [@dabrahams](https://forums.swift.org/u/dabrahams)\ **Post date:** [February 5, 2016, 12:11am UTC](https://forums.swift.org/t/accepted-se-0028-modernizing-swifts-debugging-identifiers-line-etc/1303/12 "2016-02-05T00:11:09Z")
OK. > **···** > > on Thu Feb 04 2016, Chris Lattner \ wrote: > > > > On Feb 4, 2016, at 11:17 AM, Dave Abrahams \>\> \ wrote: > > > > > > > On Feb 4, 2016, at 9:29 AM, Chris Lattner \> \>\>\> \\>\> \\> wrote: > > > > > > > > > On Feb 4, 2016, at 7:03 AM, Erica Sadun via swift-evolution \>\>\>\> \\>\>\> \\> \>\>\>\> wrote: > > > > > > > > > > > On Feb 4, 2016, at 1:24 AM, Dave Abrahams via swift-evolution \>\>\>\>\> \\>\>\>\> \\> \>\>\>\>\> wrote: > > > > > > > > > > > > I'm afraid we'll ultimately need to solve this some other way than by > > > > > > choosing a different name. We're eventually going to end up with > > > > > > something meaning #sourceLocation (modulo capitalization) and that's > > > > > > obviously (IMO) going to be the right name for both entities. > > > > > > > > I don’t agree with you Dave, these are certainly related, but also > > > > very different operations. > > > > > > They both represent source locations. > > > > No, they don’t, at least not in the same way. The directive only > > contains the file and line. The expressions can produce the column > > and function. > > > > These are related, but different. > > -- > -Dave