Tony has a set of inbox submissions in Kernel, Multilingual, and MultilingualTests that appear to be ready to move to trunk.

Should we move these to trunk? If no objections I will move them a few days from now if no one else has gotten to it by then.

There will be some new test failures for UTF8EdgeCaseTest, which is a good thing since these are new tests that document existing issues.

Dave

On Thu, Feb 01, 2018 at 10:02:22AM +0000, Tony Garnock-Jones wrote:

Hi Eliot,

On 02/01/2018 12:34 AM, Eliot Miranda wrote:

...

+?? ?? ?? ??(arg isKindOf: Promise)

I'd /much/ rather see Object>>isPromise and Promise>>isPromise than this.

Excellent point! Thanks.

There is a Promise>>isPromise, but no matching Object>>isPromise.

Kernel-tonyg.1150 (just committed to Inbox) reintroduces it, and switches from using isKindOf: to using isPromise.

This change is also in keeping with the spirit of Promises/A+, where anything that is "thenable" is treated as promise-like.

Tony

+1 for #isPromise

I don't think we need the #isKindOf: "flavor" here because the basic concept seems to be quite mature and thus justifies the addition to the Object protocol.

(For other discussions about #isKindOf: see the history of the mailing list. There was at least one in combination with Morphic Flaps.)

Best, Marcel Am 01.02.2018 01:34:33 schrieb Eliot Miranda eliot.miranda@gmail.com: Hi Tony,

On Wed, Jan 31, 2018 at 3:37 PM, <commits@source.squeak.org [mailto:commits@source.squeak.org]> wrote:

A new version of Kernel was added to project The Inbox: http://source.squeak.org/inbox/Kernel-tonyg.1148.mcz [http://source.squeak.org/inbox/Kernel-tonyg.1148.mcz]

==================== Summary ====================

Name: Kernel-tonyg.1148 Author: tonyg Time: 31 January 2018, 11:37:21.27021 pm UUID: 2a675301-406b-4222-9599-84358a7cc506 Ancestors: Kernel-eem.1147

Brings the Promise implementation closer to Javascript/A+ promises in two ways:         * Resolving a Promise with another Promise causes them to be chained together         * Resolving or Rejecting a Promise that is not pending is a no-op, like the Firefox/Chrome/etc in-browser promise implementations. The tests have been changed in KernelTests-tonyg.331 accordingly.

=============== Diff against Kernel-eem.1147 ===============

Item was changed:   Object subclass: #Promise +       instanceVariableNames: 'value resolvers mutex state error rejecters' -       instanceVariableNames: 'onError value resolvers mutex state error rejectors rejecters'         classVariableNames: ''         poolDictionaries: ''         category: 'Kernel-Processes'!

+ !Promise commentStamp: 'tonyg 1/31/2018 23:34' prior: 0! - !Promise commentStamp: 'fbs 5/17/2013 18:23' prior: 0!   I represent the result of an asynchronous message.  Once the message is processed, I will be resolved to a value.  I am typically instantiated by invocations of #futureSend:at:args: (and not by #futureDo:atArgs:).

See class-comment of FutureNode.

I also implement the Promises/A+ Javascript specification. This allows you to chain my instances to perform arbitrarily complex asynchronous tasks with error handling baked in.

+ A Promise may be in one of three possible states: #pending, #fulfilled or #rejected. A Promise may move from #pending -> #fulfilled (by way of the resolveWith: message), or from #pending -> #rejected (by way of rejectWith:). No other state changes may occur. + + Once #fulfilled or #rejected, a Promise's value must not change. In keeping with the major Javascript Promise implementations' interpretations of this, calls to resolveWith: or rejectWith: when a Promise is in #fulfilled or #rejected state are simply ignored - an error is not signalled. (See test cases PromiseTest testFirstResolutionWins, testCannotRejectFulfilledPromise and testCannotResolveaRejectedPromise.)! - A Promise may be in one of three possible states: #pending, #fulfilled or #rejected. A Promise may move from #pending -> #fulfilled, or from #pending -> #rejected. No other state changes may occur. Once #fulfilled or #rejected, a Promise's value must change.!

Item was changed:   ----- Method: Promise>>rejectWith: (in category 'resolving') -----   rejectWith: anObject         "Reject this promise."         mutex critical: [ +               (state == #pending) ifTrue: [ +                       error := anObject. +                       state := #rejected. +                       rejecters do: [:r | self evaluateRejecter: r]]]! -               (state == #fulfilled) ifTrue: [self error: 'Promise was already resolved']. -               (state == #rejected) ifTrue: [self error: 'Promise was already rejected']. -               error := anObject. -               state := #rejected. -               rejecters do: [:r | self evaluateRejecter: r]].!

Item was changed:   ----- Method: Promise>>resolveWith: (in category 'resolving') -----   resolveWith: arg +       "Resolve this promise. If arg is itself a Promise, make this promise depend upon it, +       as detailed in the Promises/A+ spec: +               https://promisesaplus.com/#the-promise-resolution-procedure [https://promisesaplus.com/#the-promise-resolution-procedure]" + +       (arg isKindOf: Promise)

I'd /much/ rather see Object>>isPromise and Promise>>isPromise than this.   +               ifTrue: [ +                       arg whenResolved: [:v | self resolveWith: v]. +                       arg whenRejected: [:e | self rejectWith: e]] +               ifFalse: [ +                       mutex critical: [ +                               (state == #pending) ifTrue: [ +                                       value := arg. +                                       state := #fulfilled. +                                       resolvers do: [:r | self evaluateResolver: r]]]]! -       "Resolve this promise" -       mutex critical: [ -               (state == #fulfilled) ifTrue: [self error: 'Promise was already resolved']. -               (state == #rejected) ifTrue: [self error: 'Promise was already resolved']. -               value := arg. -               state := #fulfilled. -               resolvers do: [:r | -                       self evaluateResolver: r]].!

Item was changed:   ----- Method: Promise>>then: (in category 'monad') -----   then: resolvedBlock +       ^ self then: resolvedBlock ifRejected: [:e | "Pass rejection reason along" e].! -       ^ self then: resolvedBlock ifRejected: [:ignored | "Do nothing"].!

_,,,^..^,,,_

best, Eliot