[Review] SE-0148 Generic Subscripts

Douglas_Gregor · 2017-01-19T21:39:36.000Z

Hello Swift community,

The review of SE-0148 “Generic Subscripts" begins now and runs through January 24, 2017. The proposal is available here:

swift-evolution/0148-generic-subscripts.md at master · apple/swift-evolution · GitHub <https://github.com/apple/swift-evolution/blob/master/proposals/NNNN-proposal.md>
Reviews are an important part of the Swift evolution process. All reviews should be sent to the swift-evolution mailing list at

https://lists.swift.org/mailman/listinfo/swift-evolution
or, if you would like to keep your feedback private, directly to the review manager. When replying, please try to keep the proposal link at the top of the message:

Proposal link:

swift-evolution/0148-generic-subscripts.md at master · apple/swift-evolution · GitHub <https://github.com/apple/swift-evolution/blob/master/proposals/NNNN-proposal.md>
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<GitHub - apple/swift-evolution: This maintains proposals for changes and user-visible enhancements to the Swift Programming Language. goes into a review?

The goal of the review process is to improve the proposal under review through constructive criticism and, eventually, determine the direction of Swift. When writing your review, here are some questions you might want to answer in your review:

What is your evaluation of the proposal?
Is the problem being addressed significant enough to warrant a change to Swift?
Does this proposal fit well with the feel and direction of Swift?
If you have used other languages or libraries with a similar feature, how do you feel that this proposal compares to those?
How much effort did you put into your review? A glance, a quick reading, or an in-depth study?
More information about the Swift evolution process is available at

github.com

apple/swift-evolution/blob/master/process.md

# Swift Evolution Process

Swift is a powerful and intuitive programming language that is designed to make writing and maintaining correct programs easier. Swift is growing and evolving, guided by a community-driven process referred to as the Swift evolution process. This document outlines the Swift evolution process and how a feature grows from a rough idea into something that can improve the Swift development experience for millions of programmers.

## Scope

The Swift evolution process covers all changes to the Swift language and the public interface of the Swift standard library, including new language features and APIs (no matter how small), changes to existing language features or APIs, removal of existing features, and so on. Smaller changes, such as bug fixes, optimizations, or diagnostic improvements can be contributed via the normal contribution process; see [Contributing to Swift](https://swift.org/community/#contributing).

## Goals

The Swift evolution process aims to leverage the collective ideas, insights, and experience of the Swift community to improve the Swift development experience. Its two primary goals are:

* Engage the wider Swift community in the ongoing evolution of Swift, and
* Maintain the vision and conceptual coherence of Swift.

There is a natural tension between these two goals. Open evolution processes are, by nature, chaotic. Yet, maintaining a coherent vision for something as complicated as a programming language requires some level of coordination. The Swift evolution process aims to strike a balance that best serves the Swift community as a whole.

## Participation

Everyone is welcome to propose, discuss, and review ideas to improve

This file has been truncated. show original

Thank you,

-Doug

Review Manager

Douglas_Gregor · 2017-01-19T22:05:55.000Z

My apologies for the broken link:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md

- Doug

···

On Jan 19, 2017, at 1:39 PM, Douglas Gregor via swift-evolution <swift-evolution@swift.org> wrote:

Hello Swift community,

The review of SE-0148 “Generic Subscripts" begins now and runs through January 24, 2017. The proposal is available here:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md <https://github.com/apple/swift-evolution/blob/master/proposals/NNNN-proposal.md>
Reviews are an important part of the Swift evolution process. All reviews should be sent to the swift-evolution mailing list at

https://lists.swift.org/mailman/listinfo/swift-evolution
or, if you would like to keep your feedback private, directly to the review manager. When replying, please try to keep the proposal link at the top of the message:

Proposal link:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md <https://github.com/apple/swift-evolution/blob/master/proposals/NNNN-proposal.md>
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<GitHub - apple/swift-evolution: This maintains proposals for changes and user-visible enhancements to the Swift Programming Language. goes into a review?

The goal of the review process is to improve the proposal under review through constructive criticism and, eventually, determine the direction of Swift. When writing your review, here are some questions you might want to answer in your review:

What is your evaluation of the proposal?
Is the problem being addressed significant enough to warrant a change to Swift?
Does this proposal fit well with the feel and direction of Swift?
If you have used other languages or libraries with a similar feature, how do you feel that this proposal compares to those?
How much effort did you put into your review? A glance, a quick reading, or an in-depth study?
More information about the Swift evolution process is available at

https://github.com/apple/swift-evolution/blob/master/process.md
Thank you,

-Doug

Review Manager

_______________________________________________
swift-evolution mailing list
swift-evolution@swift.org
https://lists.swift.org/mailman/listinfo/swift-evolution

anandabits · 2017-01-19T21:58:10.000Z

What is your evaluation of the proposal?

Very enthusiastic +1. I have wanted this feature ever since Swift was released and I noticed that it was missing.

I think the proposal could be made stronger by including some of the examples that were shared in the pre-review discussion. Any reviewers who have questions about how this feature might be used should read through that discussion if they have not already done so.

Is the problem being addressed significant enough to warrant a change to Swift?

Yes. I am not aware of any significant reasons not to include this feature and am aware of several compelling use cases for it.

Does this proposal fit well with the feel and direction of Swift?

Very much so.

If you have used other languages or libraries with a similar feature, how do you feel that this proposal compares to those?

N/A

How much effort did you put into your review? A glance, a quick reading, or an in-depth study?

A quick read, but I have been missing this feature ever since Swift was released and I noticed that it was missing.

Slava_Pestov · 2017-01-20T01:04:08.000Z

Can we also add mention that default arguments on subscripts should work as well? This will force whoever implements this to do it properly and rip out the old RValue-based argument tuple emission that’s only used for subscripts in favor the argument emission logic.

Slava

···

On Jan 19, 2017, at 1:39 PM, Douglas Gregor via swift-evolution <swift-evolution@swift.org> wrote:

Hello Swift community,

The review of SE-0148 “Generic Subscripts" begins now and runs through January 24, 2017. The proposal is available here:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md <https://github.com/apple/swift-evolution/blob/master/proposals/NNNN-proposal.md>
Reviews are an important part of the Swift evolution process. All reviews should be sent to the swift-evolution mailing list at

https://lists.swift.org/mailman/listinfo/swift-evolution
or, if you would like to keep your feedback private, directly to the review manager. When replying, please try to keep the proposal link at the top of the message:

Proposal link:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md <https://github.com/apple/swift-evolution/blob/master/proposals/NNNN-proposal.md>
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<GitHub - apple/swift-evolution: This maintains proposals for changes and user-visible enhancements to the Swift Programming Language. goes into a review?

The goal of the review process is to improve the proposal under review through constructive criticism and, eventually, determine the direction of Swift. When writing your review, here are some questions you might want to answer in your review:

What is your evaluation of the proposal?
Is the problem being addressed significant enough to warrant a change to Swift?
Does this proposal fit well with the feel and direction of Swift?
If you have used other languages or libraries with a similar feature, how do you feel that this proposal compares to those?
How much effort did you put into your review? A glance, a quick reading, or an in-depth study?
More information about the Swift evolution process is available at

https://github.com/apple/swift-evolution/blob/master/process.md
Thank you,

-Doug

Review Manager

_______________________________________________
swift-evolution mailing list
swift-evolution@swift.org
https://lists.swift.org/mailman/listinfo/swift-evolution

allevato · 2017-01-19T21:52:21.000Z

Hello Swift community,

The review of SE-0148 “Generic Subscripts" begins now and runs through
January 24, 2017. The proposal is available here:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md
<https://github.com/apple/swift-evolution/blob/master/proposals/NNNN-proposal.md>

Reviews are an important part of the Swift evolution process. All reviews
should be sent to the swift-evolution mailing list at

https://lists.swift.org/mailman/listinfo/swift-evolution

or, if you would like to keep your feedback private, directly to the
review manager. When replying, please try to keep the proposal link at the
top of the message:

Proposal link:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md
<https://github.com/apple/swift-evolution/blob/master/proposals/NNNN-proposal.md>

Reply text

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<GitHub - apple/swift-evolution: This maintains proposals for changes and user-visible enhancements to the Swift Programming Language.
goes into a review?

The goal of the review process is to improve the proposal under review
through constructive criticism and, eventually, determine the direction of
Swift. When writing your review, here are some questions you might want to
answer in your review:

- What is your evaluation of the proposal?

Big +1. The proposal is short and sweet because it's obvious that we

should have this. Just look at that low bug number! :)

- Is the problem being addressed significant enough to warrant a
change to Swift?

Absolutely. This is an important part of generics (as well as just for

collection types in general) and will make a lot of things cleanly possible
that currently aren't.

- Does this proposal fit well with the feel and direction of Swift?

Yes.

- If you have used other languages or libraries with a similar
feature, how do you feel that this proposal compares to those?

The closest I can think of is having an operator overload in C++ that is

template-based. It makes sense to have the same functionality in Swift.

···

On Thu, Jan 19, 2017 at 1:39 PM Douglas Gregor via swift-evolution < swift-evolution@swift.org> wrote:

- How much effort did you put into your review? A glance, a quick
reading, or an in-depth study?

Quick read of the proposal, followed the mailing list threads.

More information about the Swift evolution process is available at

https://github.com/apple/swift-evolution/blob/master/process.md

Thank you,

-Doug

Review Manager
_______________________________________________
swift-evolution mailing list
swift-evolution@swift.org
https://lists.swift.org/mailman/listinfo/swift-evolution

David_Sweeris · 2017-01-20T04:16:35.000Z

+1, both to this proposal and Slava's suggestion.

- Dave Sweeris

···

On Jan 19, 2017, at 15:39, Douglas Gregor <dgregor@apple.com> wrote:

Hello Swift community,

The review of SE-0148 “Generic Subscripts" begins now and runs through January 24, 2017. The proposal is available here:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md

hlovatt · 2017-01-20T00:05:06.000Z

github.com

apple/swift-evolution/blob/main/proposals/0148-generic-subscripts.md

# Generic Subscripts

* Proposal: [SE-0148](0148-generic-subscripts.md)
* Author: [Chris Eidhof](https://github.com/chriseidhof)
* Review Manager: [Doug Gregor](https://github.com/DougGregor)
* Status: **Implemented (Swift 4)**
* Decision Notes: [Rationale](https://forums.swift.org/t/accepted-se-0148-generic-subscripts/5017)
* Bug: [SR-115](https://bugs.swift.org/browse/SR-115)

## Introduction

Make it possible to have generic subscripts. Example:

```swift
extension Collection {
  subscript<Indices: Sequence>(indices: Indices) -> [Iterator.Element] where Indices.Iterator.Element == Index {
    // ...
  }
}
```

This file has been truncated. show original

What is your evaluation of the proposal?

Well written proposal.

Would suggest that you add some more examples from the discussions on the mailing list, particularly the Brent-Royal TypedDictionary example.

+1 overall.

Is the problem being addressed significant enough to warrant a change to Swift?

Yes, it has caused me to write code that uses functions rather than subscripts that aren't 'natural' in Swift.

Does this proposal fit well with the feel and direction of Swift?

Yes brings subscripts more into line with functions. Could go further and include throws as well, another issue I have had!

If you have used other languages or libraries with a similar feature, how do you feel that this proposal compares to those?

Yes. Scala has generic subscripting. In Scala a read subscript calls the `apply` method and a write subscript calls the `update` method. Both `apply` and `update` can have generic arguments, can throw etc, and they do not need to have the same argument types (they are seperate methods). Generic subscripting works well in Scala but is not widely used, the vast majority of the time current Swift like subscripting is used (except that throwing is used for index out of bounds rather than terminating the program).

How much effort did you put into your review? A glance, a quick reading, or an in-depth study?

Read the evolution thread and the proposal. Have encountered this limitation in my own code.

-- Howard.

···

On 20 Jan 2017, at 8:39 am, Douglas Gregor <dgregor@apple.com> wrote:

Hello Swift community,

The review of SE-0148 “Generic Subscripts" begins now and runs through January 24, 2017. The proposal is available here:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md
Reviews are an important part of the Swift evolution process. All reviews should be sent to the swift-evolution mailing list at

https://lists.swift.org/mailman/listinfo/swift-evolution
or, if you would like to keep your feedback private, directly to the review manager. When replying, please try to keep the proposal link at the top of the message:

Proposal link:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md
Reply text

Other replies
What goes into a review?

The goal of the review process is to improve the proposal under review through constructive criticism and, eventually, determine the direction of Swift. When writing your review, here are some questions you might want to answer in your review:

What is your evaluation of the proposal?
Is the problem being addressed significant enough to warrant a change to Swift?
Does this proposal fit well with the feel and direction of Swift?
If you have used other languages or libraries with a similar feature, how do you feel that this proposal compares to those?
How much effort did you put into your review? A glance, a quick reading, or an in-depth study?
More information about the Swift evolution process is available at

https://github.com/apple/swift-evolution/blob/master/process.md
Thank you,

-Doug

Review Manager

_______________________________________________
swift-evolution-announce mailing list
swift-evolution-announce@swift.org
https://lists.swift.org/mailman/listinfo/swift-evolution-announce

Radek_Pietruszewski · 2017-01-20T10:27:02.000Z

I’m +1 for the proposal.

Context, in case it’s useful for anyone: My particular use case for generic subscripts is with my SwiftyUserDefaults library (https://github.com/radex/SwiftyUserDefaults\), which allows users to access user defaults with a syntax like: `Defaults[.foo]` and `Defaults[.foo] = 20`, in a type-safe way. `.foo` refers to a `DefaultsKey<T>` object, where T is the type stored in the user defaults. Right now, I’m forced to define multiple subscripts to support the standard types of user defaults, but it takes a lot of boilerplate code. Generic subscripts would abstract this away (with a help of a protocol to mark which types are supported). There’s also no good way to allow nested types like `[String]` or `[String: [Int]]`.

Best,
— Radek

···

On 19 Jan 2017, at 22:39, Douglas Gregor via swift-evolution <swift-evolution@swift.org> wrote:

Hello Swift community,

The review of SE-0148 “Generic Subscripts" begins now and runs through January 24, 2017. The proposal is available here:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md <https://github.com/apple/swift-evolution/blob/master/proposals/NNNN-proposal.md>
Reviews are an important part of the Swift evolution process. All reviews should be sent to the swift-evolution mailing list at

https://lists.swift.org/mailman/listinfo/swift-evolution
or, if you would like to keep your feedback private, directly to the review manager. When replying, please try to keep the proposal link at the top of the message:

Proposal link:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md <https://github.com/apple/swift-evolution/blob/master/proposals/NNNN-proposal.md>
Reply text

Other replies
<GitHub - apple/swift-evolution: This maintains proposals for changes and user-visible enhancements to the Swift Programming Language. goes into a review?

The goal of the review process is to improve the proposal under review through constructive criticism and, eventually, determine the direction of Swift. When writing your review, here are some questions you might want to answer in your review:

What is your evaluation of the proposal?
Is the problem being addressed significant enough to warrant a change to Swift?
Does this proposal fit well with the feel and direction of Swift?
If you have used other languages or libraries with a similar feature, how do you feel that this proposal compares to those?
How much effort did you put into your review? A glance, a quick reading, or an in-depth study?
More information about the Swift evolution process is available at

https://github.com/apple/swift-evolution/blob/master/process.md
Thank you,

-Doug

Review Manager

_______________________________________________
swift-evolution mailing list
swift-evolution@swift.org
https://lists.swift.org/mailman/listinfo/swift-evolution

gwendal.roue · 2017-01-20T11:03:01.000Z

github.com

apple/swift-evolution/blob/main/proposals/0148-generic-subscripts.md

# Generic Subscripts

* Proposal: [SE-0148](0148-generic-subscripts.md)
* Author: [Chris Eidhof](https://github.com/chriseidhof)
* Review Manager: [Doug Gregor](https://github.com/DougGregor)
* Status: **Implemented (Swift 4)**
* Decision Notes: [Rationale](https://forums.swift.org/t/accepted-se-0148-generic-subscripts/5017)
* Bug: [SR-115](https://bugs.swift.org/browse/SR-115)

## Introduction

Make it possible to have generic subscripts. Example:

```swift
extension Collection {
  subscript<Indices: Sequence>(indices: Indices) -> [Iterator.Element] where Indices.Iterator.Element == Index {
    // ...
  }
}
```

This file has been truncated. show original

• What is your evaluation of the proposal?

+1 Enthousiastic!

• Is the problem being addressed significant enough to warrant a change to Swift?

Yes, because library developers are required to declare generic methods, even when a subscript would look and feel more natural at the call site.

• Does this proposal fit well with the feel and direction of Swift?

Yes, because consistency simplifies the language: there was no good reason for subscripts not te be generic, except implementation details of the Swift compiler.

I'll use the same arguments to support throwing subscripts.

• If you have used other languages or libraries with a similar feature, how do you feel that this proposal compares to those?

No, I don't.

• How much effort did you put into your review? A glance, a quick reading, or an in-depth study?

I've been waiting this for years, for the SQLite library GitHub - groue/GRDB.swift: A toolkit for SQLite databases, with a focus on application development

Cheers,
Gwendal

gmosx · 2017-01-20T16:39:43.000Z

What is your evaluation of the proposal?

+1

Is the problem being addressed significant enough to warrant a change to Swift?

Yes, generic subscripts are often useful.

Does this proposal fit well with the feel and direction of Swift?

It definitely fits with Swift’s aim to be consistent, logical, non-surprising language.
Always felt like a strange omission

If you have used other languages or libraries with a similar feature, how do you feel that this proposal compares to those?

Not sure

How much effort did you put into your review? A glance, a quick reading, or an in-depth study?

Read the proposal, followed the evolution thread.

George.

Brent_Royal-Gordon · 2017-01-21T13:31:43.000Z

• What is your evaluation of the proposal?

Badly needed. I can't count how many times I've wanted this feature. And now is definitely the time to do it, because we'll need it for some upcoming standard library redesigns.

• Is the problem being addressed significant enough to warrant a change to Swift?

Yes.

• Does this proposal fit well with the feel and direction of Swift?

Yes.

• If you have used other languages or libraries with a similar feature, how do you feel that this proposal compares to those?

I haven't used many strongly-typed languages with sophisticated syntax.

• How much effort did you put into your review? A glance, a quick reading, or an in-depth study?

Quick reading. I mean, besides the days I've put in refining workarounds for this feature's absence.

···

On Jan 19, 2017, at 1:39 PM, Douglas Gregor <dgregor@apple.com> wrote:

--
Brent Royal-Gordon
Architechies

codafi · 2017-01-22T07:10:17.000Z

~Robert Widmann

2017/01/19 16:39、Douglas Gregor via swift-evolution <swift-evolution@swift.org> のメッセージ:

What is your evaluation of the proposal?

+1. A badly-needed feature for a lot of folks (and their DSLs!)

Is the problem being addressed significant enough to warrant a change to Swift?

Yes.

Does this proposal fit well with the feel and direction of Swift?

Yes.

If you have used other languages or libraries with a similar feature, how do you feel that this proposal compares to those?

Subscripts are usually not in a special class of their own in languages either with extensible syntax or operator definitions. In that case, we're just aligning ourselves with the field.

How much effort did you put into your review? A glance, a quick reading, or an in-depth study?

A quick once-through.

···

More information about the Swift evolution process is available at

https://github.com/apple/swift-evolution/blob/master/process.md
Thank you,

-Doug

Review Manager

_______________________________________________
swift-evolution mailing list
swift-evolution@swift.org
https://lists.swift.org/mailman/listinfo/swift-evolution

Karl · 2017-01-22T16:28:07.000Z

What is your evaluation of the proposal?

+1

Is the problem being addressed significant enough to warrant a change to Swift?

Yes

Does this proposal fit well with the feel and direction of Swift?

Yes

If you have used other languages or libraries with a similar feature, how do you feel that this proposal compares to those?

N/A

How much effort did you put into your review? A glance, a quick reading, or an in-depth study?

Quick read (it’s a short proposal), participated in previous discussion.

- Karl

dabrahams · 2017-01-20T00:25:51.000Z

+1; let's do it.

The proposal ought to mention

github.com

apple/swift-evolution/blob/9cf2685293108ea3efcbebb7ee6a8618b83d4a90/proposals/0132-sequence-end-ops.md

# Rationalizing Sequence end-operation names

* Proposal: [SE-0132](0132-sequence-end-ops.md)
* Authors: [Brent Royal-Gordon](https://github.com/brentdax), [Dave Abrahams](https://github.com/dabrahams)
* Review Manager: [Chris Lattner](http://github.com/lattner)
* Status: **Deferred**
* Decision Notes: [Rationale](https://lists.swift.org/pipermail/swift-evolution-announce/2016-July/000267.html)

## Introduction

Sequence and Collection offer many special operations which access or 
manipulate its first or last elements, but they are plagued by 
inconsistent naming which can make it difficult to find inverses or 
remember what the standard library offers. We propose that we standardize 
these names so they follow consistent, predictable patterns.

Swift-evolution thread: [[Draft] Rationalizing Sequence end-operation names](https://lists.swift.org/pipermail/swift-evolution/Week-of-Mon-20160620/021872.html)

### Scope

This file has been truncated. show original

as an important motivation.

···

on Thu Jan 19 2017, Douglas Gregor <swift-evolution@swift.org> wrote:

My apologies for the broken link:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md

- Doug

--
-Dave

Douglas_Gregor · 2017-01-20T03:19:43.000Z

Can we also add mention that default arguments on subscripts should work as well? This will force whoever implements this to do it properly and rip out the old RValue-based argument tuple emission that’s only used for subscripts in favor the argument emission logic.

Yeah, that seems totally reasonable to me.

- Doug

···

Sent from my iPhone

On Jan 19, 2017, at 5:04 PM, Slava Pestov <spestov@apple.com> wrote:

Slava

On Jan 19, 2017, at 1:39 PM, Douglas Gregor via swift-evolution <swift-evolution@swift.org> wrote:

Hello Swift community,

The review of SE-0148 “Generic Subscripts" begins now and runs through January 24, 2017. The proposal is available here:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md
Reviews are an important part of the Swift evolution process. All reviews should be sent to the swift-evolution mailing list at

https://lists.swift.org/mailman/listinfo/swift-evolution
or, if you would like to keep your feedback private, directly to the review manager. When replying, please try to keep the proposal link at the top of the message:

Proposal link:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md
Reply text

Other replies
What goes into a review?

The goal of the review process is to improve the proposal under review through constructive criticism and, eventually, determine the direction of Swift. When writing your review, here are some questions you might want to answer in your review:

What is your evaluation of the proposal?
Is the problem being addressed significant enough to warrant a change to Swift?
Does this proposal fit well with the feel and direction of Swift?
If you have used other languages or libraries with a similar feature, how do you feel that this proposal compares to those?
How much effort did you put into your review? A glance, a quick reading, or an in-depth study?
More information about the Swift evolution process is available at

https://github.com/apple/swift-evolution/blob/master/process.md
Thank you,

-Doug

Review Manager

_______________________________________________
swift-evolution mailing list
swift-evolution@swift.org
https://lists.swift.org/mailman/listinfo/swift-evolution

Russ_Bishop1 · 2017-01-20T06:32:58.000Z

Fully agree, +1 to the proposal and +1 to Slava’s suggestion.

Russ

···

On Jan 19, 2017, at 5:04 PM, Slava Pestov via swift-evolution <swift-evolution@swift.org> wrote:

Can we also add mention that default arguments on subscripts should work as well? This will force whoever implements this to do it properly and rip out the old RValue-based argument tuple emission that’s only used for subscripts in favor the argument emission logic.

Slava

griotspeak · 2017-01-20T05:00:33.000Z

+1 for the proposal and default arguments on subscripts

···

On Thu, Jan 19, 2017 at 11:16 PM, David Sweeris via swift-evolution < swift-evolution@swift.org> wrote:

On Jan 19, 2017, at 15:39, Douglas Gregor <dgregor@apple.com> wrote:

Hello Swift community,

The review of SE-0148 “Generic Subscripts" begins now and runs through
January 24, 2017. The proposal is available here:

GitHub - apple/swift-evolution: This maintains proposals for changes and user-visible enhancements to the Swift Programming Language.
proposals/0148-generic-subscripts.md
<https://github.com/apple/swift-evolution/blob/master/proposals/NNNN-proposal.md>

+1, both to this proposal and Slava's suggestion.

- Dave Sweeris

_______________________________________________
swift-evolution mailing list
swift-evolution@swift.org
https://lists.swift.org/mailman/listinfo/swift-evolution

Shawn_Erickson · 2017-01-20T03:18:17.000Z

Big +1 to the proposal and +1 to support default values.

···

On Thu, Jan 19, 2017 at 5:04 PM Slava Pestov via swift-evolution < swift-evolution@swift.org> wrote:

Can we also add mention that default arguments on subscripts should work
as well? This will force whoever implements this to do it properly and rip
out the old RValue-based argument tuple emission that’s only used for
subscripts in favor the argument emission logic.

Slava

On Jan 19, 2017, at 1:39 PM, Douglas Gregor via swift-evolution < > swift-evolution@swift.org> wrote:

Hello Swift community,

The review of SE-0148 “Generic Subscripts" begins now and runs through
January 24, 2017. The proposal is available here:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md
<https://github.com/apple/swift-evolution/blob/master/proposals/NNNN-proposal.md>

Reviews are an important part of the Swift evolution process. All reviews
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Proposal link:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md
<https://github.com/apple/swift-evolution/blob/master/proposals/NNNN-proposal.md>

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Chris_Eidhof · 2017-01-20T07:53:02.000Z

Hey all,

I've added a PR which consists of two commits: one that mentions more
examples, and one that adds a note about including default arguments.

···

On Fri, Jan 20, 2017 at 7:32 AM, Russ Bishop via swift-evolution < swift-evolution@swift.org> wrote:

> On Jan 19, 2017, at 5:04 PM, Slava Pestov via swift-evolution < > swift-evolution@swift.org> wrote:
>
> Can we also add mention that default arguments on subscripts should work
as well? This will force whoever implements this to do it properly and rip
out the old RValue-based argument tuple emission that’s only used for
subscripts in favor the argument emission logic.
>
> Slava

Fully agree, +1 to the proposal and +1 to Slava’s suggestion.

Russ

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--
Chris Eidhof

Erica_Sadun · 2017-01-23T20:46:31.000Z

+1. The change offers notable utility, I have read the proposal, and it fits with the direction of Swift.

-- E

···

On Jan 19, 2017, at 5:25 PM, Dave Abrahams via swift-evolution <swift-evolution@swift.org> wrote:

on Thu Jan 19 2017, Douglas Gregor <swift-evolution@swift.org> wrote:

My apologies for the broken link:

https://github.com/apple/swift-evolution/blob/master/proposals/0148-generic-subscripts.md

- Doug

+1; let's do it.

The proposal ought to mention
https://github.com/apple/swift-evolution/blob/9cf2685293108ea3efcbebb7ee6a8618b83d4a90/proposals/0132-sequence-end-ops.md
as an important motivation.