The Inbox: ShoutCore-ct.69.mcz

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The Inbox: ShoutCore-ct.69.mcz

commits-2
A new version of ShoutCore was added to project The Inbox:
http://source.squeak.org/inbox/ShoutCore-ct.69.mcz

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

Name: ShoutCore-ct.69
Author: ct
Time: 14 August 2019, 10:43:04.7164 pm
UUID: 7d165f4e-09bf-a445-a664-5e8edb9867b8
Ancestors: ShoutCore-ul.68

Fix bug in SHParserST80: Wrong styling after blocks with arguments without statements

Thanks Jakob for the report!

=============== Diff against ShoutCore-ul.68 ===============

Item was changed:
  ----- Method: SHParserST80>>parseBlockArguments (in category 'parse') -----
  parseBlockArguments
 
  currentTokenFirst == $: ifFalse: [ ^self ].
  [ currentTokenFirst == $: ] whileTrue: [
  self
  scanPast: #blockArgColon;
  parseArgument: #blockPatternArg ].
+ ((self parseVerticalBarForTemporaries: #blockArgsBar) and: [
+ currentTokenFirst ~= $] ])
+ ifFalse: [
+ self fail ": Missing block args bar" ]!
- (self parseVerticalBarForTemporaries: #blockArgsBar) ifFalse: [
- self fail ": Missing block args bar" ]!


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Re: The Inbox: ShoutCore-ct.69.mcz

Levente Uzonyi
On Wed, 14 Aug 2019, [hidden email] wrote:

> A new version of ShoutCore was added to project The Inbox:
> http://source.squeak.org/inbox/ShoutCore-ct.69.mcz
>
> ==================== Summary ====================
>
> Name: ShoutCore-ct.69
> Author: ct
> Time: 14 August 2019, 10:43:04.7164 pm
> UUID: 7d165f4e-09bf-a445-a664-5e8edb9867b8
> Ancestors: ShoutCore-ul.68
>
> Fix bug in SHParserST80: Wrong styling after blocks with arguments without statements

If you mean that Shout should accept [ :x ], then no, I'm pretty sure
that's not valid smalltalk syntax, even if Parser accepts it.
The vertical bar, even though I consider it unnecessary in all cases, is
mandatory when there are arguments.

Levente

>
> Thanks Jakob for the report!
>
> =============== Diff against ShoutCore-ul.68 ===============
>
> Item was changed:
>  ----- Method: SHParserST80>>parseBlockArguments (in category 'parse') -----
>  parseBlockArguments
>
>   currentTokenFirst == $: ifFalse: [ ^self ].
>   [ currentTokenFirst == $: ] whileTrue: [
>   self
>   scanPast: #blockArgColon;
>   parseArgument: #blockPatternArg ].
> + ((self parseVerticalBarForTemporaries: #blockArgsBar) and: [
> + currentTokenFirst ~= $] ])
> + ifFalse: [
> + self fail ": Missing block args bar" ]!
> - (self parseVerticalBarForTemporaries: #blockArgsBar) ifFalse: [
> - self fail ": Missing block args bar" ]!

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Re: The Inbox: ShoutCore-ct.69.mcz

Tobias Pape

> On 15.08.2019, at 03:29, Levente Uzonyi <[hidden email]> wrote:
>
> On Wed, 14 Aug 2019, [hidden email] wrote:
>
>> A new version of ShoutCore was added to project The Inbox:
>> http://source.squeak.org/inbox/ShoutCore-ct.69.mcz
>>
>> ==================== Summary ====================
>>
>> Name: ShoutCore-ct.69
>> Author: ct
>> Time: 14 August 2019, 10:43:04.7164 pm
>> UUID: 7d165f4e-09bf-a445-a664-5e8edb9867b8
>> Ancestors: ShoutCore-ul.68
>>
>> Fix bug in SHParserST80: Wrong styling after blocks with arguments without statements
>
> If you mean that Shout should accept [ :x ], then no, I'm pretty sure that's not valid smalltalk syntax, even if Parser accepts it.
> The vertical bar, even though I consider it unnecessary in all cases, is mandatory when there are arguments.

I only got to know this "shortcut syntax" because eliot used it either Cog or somewhere in trunk when preparing something (Spur? full block closures? I forgot). So this is a syntax idiosyncrasy that is in active use, not only "old code".

Either we forbid it in the parser and change all of the image or allow it in Shout.

Best regards
        -Tobias

>
> Levente
>
>>
>> Thanks Jakob for the report!
>>
>> =============== Diff against ShoutCore-ul.68 ===============
>>
>> Item was changed:
>> ----- Method: SHParserST80>>parseBlockArguments (in category 'parse') -----
>> parseBlockArguments
>>
>> currentTokenFirst == $: ifFalse: [ ^self ].
>> [ currentTokenFirst == $: ] whileTrue: [
>> self
>> scanPast: #blockArgColon;
>> parseArgument: #blockPatternArg ].
>> + ((self parseVerticalBarForTemporaries: #blockArgsBar) and: [
>> + currentTokenFirst ~= $] ])
>> + ifFalse: [
>> + self fail ": Missing block args bar" ]!
>> - (self parseVerticalBarForTemporaries: #blockArgsBar) ifFalse: [
>> - self fail ": Missing block args bar" ]!
>



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Re: The Inbox: ShoutCore-ct.69.mcz

Christoph Thiede

For reference, the GNU Smalltalk specification does not allow this kind of expression ([:x]). Personally, I would find the syntax clear & unique, but when developing a solution for multiple Smalltalk dialects, this might be a disadvantage.


Maybe introduce a preference similar to #allowUnderscoreAsAssignment? Or would this make the things unnecessarily complex?


Best,

Christoph


Von: Squeak-dev <[hidden email]> im Auftrag von Tobias Pape <[hidden email]>
Gesendet: Donnerstag, 15. August 2019 08:11:30
An: The general-purpose Squeak developers list
Betreff: Re: [squeak-dev] The Inbox: ShoutCore-ct.69.mcz
 

> On 15.08.2019, at 03:29, Levente Uzonyi <[hidden email]> wrote:
>
> On Wed, 14 Aug 2019, [hidden email] wrote:
>
>> A new version of ShoutCore was added to project The Inbox:
>> http://source.squeak.org/inbox/ShoutCore-ct.69.mcz
>>
>> ==================== Summary ====================
>>
>> Name: ShoutCore-ct.69
>> Author: ct
>> Time: 14 August 2019, 10:43:04.7164 pm
>> UUID: 7d165f4e-09bf-a445-a664-5e8edb9867b8
>> Ancestors: ShoutCore-ul.68
>>
>> Fix bug in SHParserST80: Wrong styling after blocks with arguments without statements
>
> If you mean that Shout should accept [ :x ], then no, I'm pretty sure that's not valid smalltalk syntax, even if Parser accepts it.
> The vertical bar, even though I consider it unnecessary in all cases, is mandatory when there are arguments.

I only got to know this "shortcut syntax" because eliot used it either Cog or somewhere in trunk when preparing something (Spur? full block closures? I forgot). So this is a syntax idiosyncrasy that is in active use, not only "old code".

Either we forbid it in the parser and change all of the image or allow it in Shout.

Best regards
        -Tobias

>
> Levente
>
>>
>> Thanks Jakob for the report!
>>
>> =============== Diff against ShoutCore-ul.68 ===============
>>
>> Item was changed:
>> ----- Method: SHParserST80>>parseBlockArguments (in category 'parse') -----
>> parseBlockArguments
>>
>>       currentTokenFirst == $: ifFalse: [ ^self ].
>>       [ currentTokenFirst == $: ] whileTrue: [
>>               self
>>                       scanPast: #blockArgColon;
>>                       parseArgument: #blockPatternArg ].
>> +     ((self parseVerticalBarForTemporaries: #blockArgsBar) and: [
>> +             currentTokenFirst ~= $] ])
>> +                     ifFalse: [
>> +                             self fail ": Missing block args bar" ]!
>> -     (self parseVerticalBarForTemporaries: #blockArgsBar) ifFalse: [
>> -             self fail ": Missing block args bar" ]!
>





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Re: The Inbox: ShoutCore-ct.69.mcz

Levente Uzonyi
In reply to this post by Tobias Pape
On Thu, 15 Aug 2019, Tobias Pape wrote:

>
>> On 15.08.2019, at 03:29, Levente Uzonyi <[hidden email]> wrote:
>>
>> On Wed, 14 Aug 2019, [hidden email] wrote:
>>
>>> A new version of ShoutCore was added to project The Inbox:
>>> http://source.squeak.org/inbox/ShoutCore-ct.69.mcz
>>>
>>> ==================== Summary ====================
>>>
>>> Name: ShoutCore-ct.69
>>> Author: ct
>>> Time: 14 August 2019, 10:43:04.7164 pm
>>> UUID: 7d165f4e-09bf-a445-a664-5e8edb9867b8
>>> Ancestors: ShoutCore-ul.68
>>>
>>> Fix bug in SHParserST80: Wrong styling after blocks with arguments without statements
>>
>> If you mean that Shout should accept [ :x ], then no, I'm pretty sure that's not valid smalltalk syntax, even if Parser accepts it.
>> The vertical bar, even though I consider it unnecessary in all cases, is mandatory when there are arguments.
>
> I only got to know this "shortcut syntax" because eliot used it either Cog or somewhere in trunk when preparing something (Spur? full block closures? I forgot). So this is a syntax idiosyncrasy that is in active use, not only "old code".
>
> Either we forbid it in the parser and change all of the image or allow it in Shout.

Can you give me examples?
I suspect those are just typos, which the parser accidentally accepted
(and Shout as well before my fixes).

Levente

>
> Best regards
> -Tobias
>
>>
>> Levente
>>
>>>
>>> Thanks Jakob for the report!
>>>
>>> =============== Diff against ShoutCore-ul.68 ===============
>>>
>>> Item was changed:
>>> ----- Method: SHParserST80>>parseBlockArguments (in category 'parse') -----
>>> parseBlockArguments
>>>
>>> currentTokenFirst == $: ifFalse: [ ^self ].
>>> [ currentTokenFirst == $: ] whileTrue: [
>>> self
>>> scanPast: #blockArgColon;
>>> parseArgument: #blockPatternArg ].
>>> + ((self parseVerticalBarForTemporaries: #blockArgsBar) and: [
>>> + currentTokenFirst ~= $] ])
>>> + ifFalse: [
>>> + self fail ": Missing block args bar" ]!
>>> - (self parseVerticalBarForTemporaries: #blockArgsBar) ifFalse: [
>>> - self fail ": Missing block args bar" ]!
>>

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Re: The Inbox: ShoutCore-ct.69.mcz

Nicolas Cellier


Le jeu. 15 août 2019 à 12:21, Levente Uzonyi <[hidden email]> a écrit :
On Thu, 15 Aug 2019, Tobias Pape wrote:

>
>> On 15.08.2019, at 03:29, Levente Uzonyi <[hidden email]> wrote:
>>
>> On Wed, 14 Aug 2019, [hidden email] wrote:
>>
>>> A new version of ShoutCore was added to project The Inbox:
>>> http://source.squeak.org/inbox/ShoutCore-ct.69.mcz
>>>
>>> ==================== Summary ====================
>>>
>>> Name: ShoutCore-ct.69
>>> Author: ct
>>> Time: 14 August 2019, 10:43:04.7164 pm
>>> UUID: 7d165f4e-09bf-a445-a664-5e8edb9867b8
>>> Ancestors: ShoutCore-ul.68
>>>
>>> Fix bug in SHParserST80: Wrong styling after blocks with arguments without statements
>>
>> If you mean that Shout should accept [ :x ], then no, I'm pretty sure that's not valid smalltalk syntax, even if Parser accepts it.
>> The vertical bar, even though I consider it unnecessary in all cases, is mandatory when there are arguments.
>
> I only got to know this "shortcut syntax" because eliot used it either Cog or somewhere in trunk when preparing something (Spur? full block closures? I forgot). So this is a syntax idiosyncrasy that is in active use, not only "old code".
>
> Either we forbid it in the parser and change all of the image or allow it in Shout.

Can you give me examples?
I suspect those are just typos, which the parser accidentally accepted
(and Shout as well before my fixes).

Levente


I don't remember seeing this syntax before and found it a bit surprising.
So, for the sake of curiosity, I tried in some other dialects.

[:x ] is accepted syntax in
- Visualworks (8.3),
- Pharo (v7 with OpalCompiler)
- Smalltalk-80 (apple v0.?)

[:x ] is invalid in
- Dolphin
- Smalltalk/X (jv branch)

So it seems that it's something originating from original Smalltalk-80, but not reproducted in non derivated dialects...

The bar is mandatory in blue book specification (see the last pages)

Capture d’écran 2019-08-18 à 17.11.53.png
So it seems that implementation did not agree with specifications for ages...
Capture d’écran 2019-08-18 à 18.56.05.png

>
> Best regards
>       -Tobias
>
>>
>> Levente
>>
>>>
>>> Thanks Jakob for the report!
>>>
>>> =============== Diff against ShoutCore-ul.68 ===============
>>>
>>> Item was changed:
>>> ----- Method: SHParserST80>>parseBlockArguments (in category 'parse') -----
>>> parseBlockArguments
>>>
>>>     currentTokenFirst == $: ifFalse: [ ^self ].
>>>     [ currentTokenFirst == $: ] whileTrue: [
>>>             self
>>>                     scanPast: #blockArgColon;
>>>                     parseArgument: #blockPatternArg ].
>>> +   ((self parseVerticalBarForTemporaries: #blockArgsBar) and: [
>>> +           currentTokenFirst ~= $] ])
>>> +                   ifFalse: [
>>> +                           self fail ": Missing block args bar" ]!
>>> -   (self parseVerticalBarForTemporaries: #blockArgsBar) ifFalse: [
>>> -           self fail ": Missing block args bar" ]!
>>



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Re: The Inbox: ShoutCore-ct.69.mcz

Levente Uzonyi
Hi Nicolas,

Thanks for investigating this.
I still think that it's just a parser bug, which is accidentally "used"
sometimes, especially because it only works when the block is empty.
Or does it work in other dialects with non-empty blocks?
Is it used in other dialects?

Levente

On Sun, 18 Aug 2019, Nicolas Cellier wrote:

>
>
> Le jeu. 15 août 2019 à 12:21, Levente Uzonyi <[hidden email]> a écrit :
>       On Thu, 15 Aug 2019, Tobias Pape wrote:
>
>       >
>       >> On 15.08.2019, at 03:29, Levente Uzonyi <[hidden email]> wrote:
>       >>
>       >> On Wed, 14 Aug 2019, [hidden email] wrote:
>       >>
>       >>> A new version of ShoutCore was added to project The Inbox:
>       >>> http://source.squeak.org/inbox/ShoutCore-ct.69.mcz
>       >>>
>       >>> ==================== Summary ====================
>       >>>
>       >>> Name: ShoutCore-ct.69
>       >>> Author: ct
>       >>> Time: 14 August 2019, 10:43:04.7164 pm
>       >>> UUID: 7d165f4e-09bf-a445-a664-5e8edb9867b8
>       >>> Ancestors: ShoutCore-ul.68
>       >>>
>       >>> Fix bug in SHParserST80: Wrong styling after blocks with arguments without statements
>       >>
>       >> If you mean that Shout should accept [ :x ], then no, I'm pretty sure that's not valid smalltalk syntax, even if Parser accepts it.
>       >> The vertical bar, even though I consider it unnecessary in all cases, is mandatory when there are arguments.
>       >
>       > I only got to know this "shortcut syntax" because eliot used it either Cog or somewhere in trunk when preparing something (Spur? full block closures? I forgot). So this is a syntax idiosyncrasy that is in active use, not only "old code".
>       >
>       > Either we forbid it in the parser and change all of the image or allow it in Shout.
>
>       Can you give me examples?
>       I suspect those are just typos, which the parser accidentally accepted
>       (and Shout as well before my fixes).
>
>       Levente
>
>
> I don't remember seeing this syntax before and found it a bit surprising.
> So, for the sake of curiosity, I tried in some other dialects.
>
> [:x ] is accepted syntax in
> - Visualworks (8.3),
> - Pharo (v7 with OpalCompiler)
> - Smalltalk-80 (apple v0.?)
>
> [:x ] is invalid in
> - Dolphin
> - Smalltalk/X (jv branch)
>
> So it seems that it's something originating from original Smalltalk-80, but not reproducted in non derivated dialects...
>
> The bar is mandatory in blue book specification (see the last pages)
>
> Capture d’écran 2019-08-18 à 17.11.53.png
> So it seems that implementation did not agree with specifications for ages...
> Capture d’écran 2019-08-18 à 18.56.05.png
>
>       >
>       > Best regards
>       >       -Tobias
>       >
>       >>
>       >> Levente
>       >>
>       >>>
>       >>> Thanks Jakob for the report!
>       >>>
>       >>> =============== Diff against ShoutCore-ul.68 ===============
>       >>>
>       >>> Item was changed:
>       >>> ----- Method: SHParserST80>>parseBlockArguments (in category 'parse') -----
>       >>> parseBlockArguments
>       >>>
>       >>>     currentTokenFirst == $: ifFalse: [ ^self ].
>       >>>     [ currentTokenFirst == $: ] whileTrue: [
>       >>>             self
>       >>>                     scanPast: #blockArgColon;
>       >>>                     parseArgument: #blockPatternArg ].
>       >>> +   ((self parseVerticalBarForTemporaries: #blockArgsBar) and: [
>       >>> +           currentTokenFirst ~= $] ])
>       >>> +                   ifFalse: [
>       >>> +                           self fail ": Missing block args bar" ]!
>       >>> -   (self parseVerticalBarForTemporaries: #blockArgsBar) ifFalse: [
>       >>> -           self fail ": Missing block args bar" ]!
>       >>
>
>
>

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Re: The Inbox: ShoutCore-ct.69.mcz

Squeak - Dev mailing list
The ANSI standard has the following rules for blocks:

<block constructor> ::= '[' <block body> ']'
<block body> ::= [<block argument>* '|'] [<temporaries>] [<statements>]

The standard does not recognize [:x] as legal syntax for a block.page21image64736448 page21image37471328 page21image64735680 page21image64733952 page21image64746816

On Aug 18, 2019, at 3:03 PM, Levente Uzonyi <[hidden email]> wrote:

Hi Nicolas,

Thanks for investigating this.
I still think that it's just a parser bug, which is accidentally "used" sometimes, especially because it only works when the block is empty.
Or does it work in other dialects with non-empty blocks?
Is it used in other dialects?

Levente

On Sun, 18 Aug 2019, Nicolas Cellier wrote:

Le jeu. 15 août 2019 à 12:21, Levente Uzonyi <[hidden email]> a écrit :
     On Thu, 15 Aug 2019, Tobias Pape wrote:

     >
     >> On 15.08.2019, at 03:29, Levente Uzonyi <[hidden email]> wrote:
     >>
     >> On Wed, 14 Aug 2019, [hidden email] wrote:
     >>
     >>> A new version of ShoutCore was added to project The Inbox:
     >>> http://source.squeak.org/inbox/ShoutCore-ct.69.mcz
     >>>
     >>> ==================== Summary ====================
     >>>
     >>> Name: ShoutCore-ct.69
     >>> Author: ct
     >>> Time: 14 August 2019, 10:43:04.7164 pm
     >>> UUID: 7d165f4e-09bf-a445-a664-5e8edb9867b8
     >>> Ancestors: ShoutCore-ul.68
     >>>
     >>> Fix bug in SHParserST80: Wrong styling after blocks with arguments without statements
     >>
     >> If you mean that Shout should accept [ :x ], then no, I'm pretty sure that's not valid smalltalk syntax, even if Parser accepts it.
     >> The vertical bar, even though I consider it unnecessary in all cases, is mandatory when there are arguments.
     >
     > I only got to know this "shortcut syntax" because eliot used it either Cog or somewhere in trunk when preparing something (Spur? full block closures? I forgot). So this is a syntax idiosyncrasy that is in active use, not only "old code".
     >
     > Either we forbid it in the parser and change all of the image or allow it in Shout.

     Can you give me examples?
     I suspect those are just typos, which the parser accidentally accepted
     (and Shout as well before my fixes).

     Levente
I don't remember seeing this syntax before and found it a bit surprising.
So, for the sake of curiosity, I tried in some other dialects.
[:x ] is accepted syntax in
- Visualworks (8.3),
- Pharo (v7 with OpalCompiler)
- Smalltalk-80 (apple v0.?)
[:x ] is invalid in
- Dolphin
- Smalltalk/X (jv branch)
So it seems that it's something originating from original Smalltalk-80, but not reproducted in non derivated dialects...
The bar is mandatory in blue book specification (see the last pages)
Capture d’écran 2019-08-18 à 17.11.53.png
So it seems that implementation did not agree with specifications for ages...
Capture d’écran 2019-08-18 à 18.56.05.png

     >
     > Best regards
     >       -Tobias
     >
     >>
     >> Levente
     >>
     >>>
     >>> Thanks Jakob for the report!
     >>>
     >>> =============== Diff against ShoutCore-ul.68 ===============
     >>>
     >>> Item was changed:
     >>> ----- Method: SHParserST80>>parseBlockArguments (in category 'parse') -----
     >>> parseBlockArguments
     >>>
     >>>     currentTokenFirst == $: ifFalse: [ ^self ].
     >>>     [ currentTokenFirst == $: ] whileTrue: [
     >>>             self
     >>>                     scanPast: #blockArgColon;
     >>>                     parseArgument: #blockPatternArg ].
     >>> +   ((self parseVerticalBarForTemporaries: #blockArgsBar) and: [
     >>> +           currentTokenFirst ~= $] ])
     >>> +                   ifFalse: [
     >>> +                           self fail ": Missing block args bar" ]!
     >>> -   (self parseVerticalBarForTemporaries: #blockArgsBar) ifFalse: [
     >>> -           self fail ": Missing block args bar" ]!
     >>



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Re: The Inbox: ShoutCore-ct.69.mcz

Squeak - Dev mailing list
The full definition from the draft standards (don’t have the standard handy) is:

<block constructor> ::= '[' <block body> ']'
<block body> ::= [<block argument>* '|'] [<temporaries>] [<statements>]
<block argument> ::= ':' identifier

The last line is on the next page of the draft.

/————————————————————/
For encrypted mail use [hidden email]
Get a free account at ProtonMail.com

On Aug 18, 2019, at 12:09, JOHN SARKELA via Squeak-dev <[hidden email]> wrote:

The ANSI standard has the following rules for blocks:

<block constructor> ::= '[' <block body> ']'
<block body> ::= [<block argument>* '|'] [<temporaries>] [<statements>]

The standard does not recognize [:x] as legal syntax for a block.<page21image64736448.png> <page21image37471328.png> <page21image64735680.png> <page21image64733952.png> <page21image64746816.png>

On Aug 18, 2019, at 3:03 PM, Levente Uzonyi <[hidden email]> wrote:

Hi Nicolas,

Thanks for investigating this.
I still think that it's just a parser bug, which is accidentally "used" sometimes, especially because it only works when the block is empty.
Or does it work in other dialects with non-empty blocks?
Is it used in other dialects?

Levente

On Sun, 18 Aug 2019, Nicolas Cellier wrote:

Le jeu. 15 août 2019 à 12:21, Levente Uzonyi <[hidden email]> a écrit :
     On Thu, 15 Aug 2019, Tobias Pape wrote:

     >
     >> On 15.08.2019, at 03:29, Levente Uzonyi <[hidden email]> wrote:
     >>
     >> On Wed, 14 Aug 2019, [hidden email] wrote:
     >>
     >>> A new version of ShoutCore was added to project The Inbox:
     >>> http://source.squeak.org/inbox/ShoutCore-ct.69.mcz
     >>>
     >>> ==================== Summary ====================
     >>>
     >>> Name: ShoutCore-ct.69
     >>> Author: ct
     >>> Time: 14 August 2019, 10:43:04.7164 pm
     >>> UUID: 7d165f4e-09bf-a445-a664-5e8edb9867b8
     >>> Ancestors: ShoutCore-ul.68
     >>>
     >>> Fix bug in SHParserST80: Wrong styling after blocks with arguments without statements
     >>
     >> If you mean that Shout should accept [ :x ], then no, I'm pretty sure that's not valid smalltalk syntax, even if Parser accepts it.
     >> The vertical bar, even though I consider it unnecessary in all cases, is mandatory when there are arguments.
     >
     > I only got to know this "shortcut syntax" because eliot used it either Cog or somewhere in trunk when preparing something (Spur? full block closures? I forgot). So this is a syntax idiosyncrasy that is in active use, not only "old code".
     >
     > Either we forbid it in the parser and change all of the image or allow it in Shout.

     Can you give me examples?
     I suspect those are just typos, which the parser accidentally accepted
     (and Shout as well before my fixes).

     Levente
I don't remember seeing this syntax before and found it a bit surprising.
So, for the sake of curiosity, I tried in some other dialects.
[:x ] is accepted syntax in
- Visualworks (8.3),
- Pharo (v7 with OpalCompiler)
- Smalltalk-80 (apple v0.?)
[:x ] is invalid in
- Dolphin
- Smalltalk/X (jv branch)
So it seems that it's something originating from original Smalltalk-80, but not reproducted in non derivated dialects...
The bar is mandatory in blue book specification (see the last pages)
Capture d’écran 2019-08-18 à 17.11.53.png
So it seems that implementation did not agree with specifications for ages...
Capture d’écran 2019-08-18 à 18.56.05.png

     >
     > Best regards
     >       -Tobias
     >
     >>
     >> Levente
     >>
     >>>
     >>> Thanks Jakob for the report!
     >>>
     >>> =============== Diff against ShoutCore-ul.68 ===============
     >>>
     >>> Item was changed:
     >>> ----- Method: SHParserST80>>parseBlockArguments (in category 'parse') -----
     >>> parseBlockArguments
     >>>
     >>>     currentTokenFirst == $: ifFalse: [ ^self ].
     >>>     [ currentTokenFirst == $: ] whileTrue: [
     >>>             self
     >>>                     scanPast: #blockArgColon;
     >>>                     parseArgument: #blockPatternArg ].
     >>> +   ((self parseVerticalBarForTemporaries: #blockArgsBar) and: [
     >>> +           currentTokenFirst ~= $] ])
     >>> +                   ifFalse: [
     >>> +                           self fail ": Missing block args bar" ]!
     >>> -   (self parseVerticalBarForTemporaries: #blockArgsBar) ifFalse: [
     >>> -           self fail ": Missing block args bar" ]!
     >>




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Re: The Inbox: ShoutCore-ct.69.mcz

Nicolas Cellier


Le lun. 19 août 2019 à 03:37, John Pfersich via Squeak-dev <[hidden email]> a écrit :
The full definition from the draft standards (don’t have the standard handy) is:

<block constructor> ::= '[' <block body> ']'
<block body> ::= [<block argument>* '|'] [<temporaries>] [<statements>]
<block argument> ::= ':' identifier

The last line is on the next page of the draft.

/————————————————————/
For encrypted mail use [hidden email]
Get a free account at ProtonMail.com

On Aug 18, 2019, at 12:09, JOHN SARKELA via Squeak-dev <[hidden email]> wrote:

The ANSI standard has the following rules for blocks:

<block constructor> ::= '[' <block body> ']'
<block body> ::= [<block argument>* '|'] [<temporaries>] [<statements>]

The standard does not recognize [:x] as legal syntax for a block.<page21image64736448.png> <page21image37471328.png> <page21image64735680.png> <page21image64733952.png> <page21image64746816.png>

Yes, same as blue book. (block temporaries apart, this did not exist in st-80), bar is mandatory.
On Aug 18, 2019, at 3:03 PM, Levente Uzonyi <[hidden email]> wrote:

Hi Nicolas,

Thanks for investigating this.
It's been a pretext for playing with historical material ;)

I still think that it's just a parser bug, which is accidentally "used" sometimes, especially because it only works when the block is empty.
Seeing the code, it's the & (hereType ~~ #rightBracket) condition following (t1 size > 0 which makes [:x ] syntax possible.
Since it has been added explicitely, my bet is that it has been added purposely and deliberataly rather than accidentally.

It seems [:x ] was not accepted in earlier version 00:
[block | blk argNodes argument |
	 " '[' {:var.} (:var|statements) ']'   BlockNode"
	argNodes ← (Vector new: 1) asStream.
	(self match: #leftBracket)
	  ifTrue:
		[[(self match: #colon) and: [((argument ← self match: #word)
		  ifTrue: [argNodes next← encoder autoBind: argument]
		  ifFalse: [↑self expected: 'Argument name'])]] whileTrueDo: [].
		(argNodes empty or: [(self match: #verticalBar)])   false
		  ifTrue: [↑self expected: 'Vertical bar'].
		((blk ← self statements: argNodes contents doit: false) and: [(self match: #rightBracket)])
		  ifTrue: [↑blk].
		↑self expected: 'Period or right bracket']
	  ifFalse: [↑self expected: 'Left bracket']].

Or does it work in other dialects with non-empty blocks?

Nope, the syntax is only for empty blocks.
It could have worked for any block if we wanted to, because that vertical bar is just a decoration in blocks.
From disambiguation POV, it's absolutely unecessary, the block arguments are already delimited by colon prefix :x
Symetrically, we don't use such delimitation between method pattern and statements... But it evolved across history:

Historically, Smalltalk-76 did use a single (optional) bar for declaring temporaries (if any):
methodDefnition := pattern [ '|' temporaries ] '[' statements ']'

Then early Smalltalk-80 method definitions did use empty temps systematically '[' pattern '|' '|' statements ']'
The two bars were mandatory at that time
"374" LADParser$'Parser'
[temporaries | vars |
	 "[ '|' {variable} ]   {variable, ..., variable}"
	(self match: #verticalBar) and: [((self match: #verticalBar)
	  ifTrue: [↑#()].
	vars ← (Vector new: 8) asStream.
	[hereType   #word] whileTrueDo: [vars next← encoder bind: self advance].
	(self match: #verticalBar)
	  ifTrue: [↑vars contents])].
	↑self expected: 'Vertical bar'].

I guess that current block syntax is the legacy from all these syntax evolutions/experiments...

Personnally, I like the bar, because it reminds me mathematical notation I learned at school for ensemble comprehension https://fr.wikipedia.org/wiki/Ensemble...

     {x ∊ E | x even }

translated in Smalltalk:

    E select: [:x | x even].

without bar, I'm really NOT used to it:

    E select: [:x x even].


Is it used in other dialects?

It is used in Squeak:

Context>>runSimulated: aBlock
     "Simulate the execution of the argument, current. Answer the result it
    returns."

     ^ thisContext sender
     runSimulated: aBlock
     contextAtEachStep: [:ignored]

     "Context runSimulated: [Pen new defaultNib: 5; go: 100]"

See also MCMcdReader>>#loadPatch MCPatch>>#initializeWithBase:target:

I also see two usages in VW, MethodContext>>#selector and BlockContext>>#selector.
The fact that these two methods still have undescore (left arrow) assignment in source code and have same argument signature [:ignored] speaks for itself!!!
I'm convinced that it's been an easy hack/feature originating in early 80s (probably by Dan Ingalls), and forgotten since, that never made it into the offical specifications.
Smalltalk is malleable enough :)

We can deprecate it if we want, but we will have to support backward compatibility in the Parser. The boring side of frozen specs...
In this case,we'd better not support it in Shout.

Levente

On Sun, 18 Aug 2019, Nicolas Cellier wrote:

Le jeu. 15 août 2019 à 12:21, Levente Uzonyi <[hidden email]> a écrit :
     On Thu, 15 Aug 2019, Tobias Pape wrote:

     >
     >> On 15.08.2019, at 03:29, Levente Uzonyi <[hidden email]> wrote:
     >>
     >> On Wed, 14 Aug 2019, [hidden email] wrote:
     >>
     >>> A new version of ShoutCore was added to project The Inbox:
     >>> http://source.squeak.org/inbox/ShoutCore-ct.69.mcz
     >>>
     >>> ==================== Summary ====================
     >>>
     >>> Name: ShoutCore-ct.69
     >>> Author: ct
     >>> Time: 14 August 2019, 10:43:04.7164 pm
     >>> UUID: 7d165f4e-09bf-a445-a664-5e8edb9867b8
     >>> Ancestors: ShoutCore-ul.68
     >>>
     >>> Fix bug in SHParserST80: Wrong styling after blocks with arguments without statements
     >>
     >> If you mean that Shout should accept [ :x ], then no, I'm pretty sure that's not valid smalltalk syntax, even if Parser accepts it.
     >> The vertical bar, even though I consider it unnecessary in all cases, is mandatory when there are arguments.
     >
     > I only got to know this "shortcut syntax" because eliot used it either Cog or somewhere in trunk when preparing something (Spur? full block closures? I forgot). So this is a syntax idiosyncrasy that is in active use, not only "old code".
     >
     > Either we forbid it in the parser and change all of the image or allow it in Shout.

     Can you give me examples?
     I suspect those are just typos, which the parser accidentally accepted
     (and Shout as well before my fixes).

     Levente
I don't remember seeing this syntax before and found it a bit surprising.
So, for the sake of curiosity, I tried in some other dialects.
[:x ] is accepted syntax in
- Visualworks (8.3),
- Pharo (v7 with OpalCompiler)
- Smalltalk-80 (apple v0.?)
[:x ] is invalid in
- Dolphin
- Smalltalk/X (jv branch)
So it seems that it's something originating from original Smalltalk-80, but not reproducted in non derivated dialects...
The bar is mandatory in blue book specification (see the last pages)
Capture d’écran 2019-08-18 à 17.11.53.png
So it seems that implementation did not agree with specifications for ages...
Capture d’écran 2019-08-18 à 18.56.05.png

     >
     > Best regards
     >       -Tobias
     >
     >>
     >> Levente
     >>
     >>>
     >>> Thanks Jakob for the report!
     >>>
     >>> =============== Diff against ShoutCore-ul.68 ===============
     >>>
     >>> Item was changed:
     >>> ----- Method: SHParserST80>>parseBlockArguments (in category 'parse') -----
     >>> parseBlockArguments
     >>>
     >>>     currentTokenFirst == $: ifFalse: [ ^self ].
     >>>     [ currentTokenFirst == $: ] whileTrue: [
     >>>             self
     >>>                     scanPast: #blockArgColon;
     >>>                     parseArgument: #blockPatternArg ].
     >>> +   ((self parseVerticalBarForTemporaries: #blockArgsBar) and: [
     >>> +           currentTokenFirst ~= $] ])
     >>> +                   ifFalse: [
     >>> +                           self fail ": Missing block args bar" ]!
     >>> -   (self parseVerticalBarForTemporaries: #blockArgsBar) ifFalse: [
     >>> -           self fail ": Missing block args bar" ]!
     >>





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Re: The Inbox: ShoutCore-ct.69.mcz

Levente Uzonyi
On Mon, 19 Aug 2019, Nicolas Cellier wrote:

>
>
> Le lun. 19 août 2019 à 03:37, John Pfersich via Squeak-dev <[hidden email]> a écrit :
>       The full definition from the draft standards (don’t have the standard handy) is:
> <block constructor> ::= '[' <block body> ']'
> <block body> ::= [<block argument>* '|'] [<temporaries>] [<statements>]
> <block argument> ::= ':' identifier
>
> The last line is on the next page of the draft.
>
> /————————————————————/For encrypted mail use [hidden email] a free account at ProtonMail.com
> Web: www.objectnets.net and www.objectnets.org
>
> On Aug 18, 2019, at 12:09, JOHN SARKELA via Squeak-dev <[hidden email]> wrote:
>
>       The ANSI standard has the following rules for blocks:
>
>       <block constructor> ::= '[' <block body> ']'
>       <block body> ::= [<block argument>* '|'] [<temporaries>] [<statements>]
>
> The standard does not recognize [:x] as legal syntax for a block.<page21image64736448.png> <page21image37471328.png> <page21image64735680.png> <page21image64733952.png> <page21image64746816.png>
>
> Yes, same as blue book. (block temporaries apart, this did not exist in st-80), bar is mandatory.
>                   On Aug 18, 2019, at 3:03 PM, Levente Uzonyi <[hidden email]> wrote:
>
> Hi Nicolas,
>
> Thanks for investigating this.
>
> It's been a pretext for playing with historical material ;)
>
>                   I still think that it's just a parser bug, which is accidentally "used" sometimes, especially because it only works when the block is empty.
>
> Seeing the code, it's the & (hereType ~~ #rightBracket) condition following (t1 size > 0 which makes [:x ] syntax possible.
> Since it has been added explicitely, my bet is that it has been added purposely and deliberataly rather than accidentally.
>
> It seems [:x ] was not accepted in earlier version 00:
>
> [block | blk argNodes argument |
> " '[' {:var.} (:var|statements) ']'   BlockNode"
> argNodes ← (Vector new: 1) asStream.
> (self match: #leftBracket)
>  ifTrue:
> [[(self match: #colon) and: [((argument ← self match: #word)
>  ifTrue: [argNodes next← encoder autoBind: argument]
>  ifFalse: [↑self expected: 'Argument name'])]] whileTrueDo: [].
> (argNodes empty or: [(self match: #verticalBar)])   false
>  ifTrue: [↑self expected: 'Vertical bar'].
> ((blk ← self statements: argNodes contents doit: false) and: [(self match: #rightBracket)])
>  ifTrue: [↑blk].
> ↑self expected: 'Period or right bracket']
>  ifFalse: [↑self expected: 'Left bracket']].
> http://xeroxalto.computerhistory.org/Indigo/BasicDisks/Smalltalk14.bfs!1_/.st80sources.v00.html
>
>                   Or does it work in other dialects with non-empty blocks?
>
>
> Nope, the syntax is only for empty blocks.
> It could have worked for any block if we wanted to, because that vertical bar is just a decoration in blocks.
> From disambiguation POV, it's absolutely unecessary, the block arguments are already delimited by colon prefix :x
> Symetrically, we don't use such delimitation between method pattern and statements... But it evolved across history:
>
> Historically, Smalltalk-76 did use a single (optional) bar for declaring temporaries (if any):
> methodDefnition := pattern [ '|' temporaries ] '[' statements ']'
>
> Then early Smalltalk-80 method definitions did use empty temps systematically '[' pattern '|' '|' statements ']'
> The two bars were mandatory at that time
>
> "374" LADParser$'Parser'
> [temporaries | vars |
> "[ '|' {variable} ]   {variable, ..., variable}"
> (self match: #verticalBar) and: [((self match: #verticalBar)
>  ifTrue: [↑#()].
> vars ← (Vector new: 8) asStream.
> [hereType   #word] whileTrueDo: [vars next← encoder bind: self advance].
> (self match: #verticalBar)
>  ifTrue: [↑vars contents])].
> ↑self expected: 'Vertical bar'].
> http://xeroxalto.computerhistory.org/Indigo/BasicDisks/Smalltalk14.bfs!1_/.st80sources.v00.html
>
> I guess that current block syntax is the legacy from all these syntax evolutions/experiments...
>
> Personnally, I like the bar, because it reminds me mathematical notation I learned at school for ensemble comprehension https://fr.wikipedia.org/wiki/Ensemble...
>
>      {x ∊ E | x even }
>
> translated in Smalltalk:
>
>     E select: [:x | x even].
>
> without bar, I'm really NOT used to it:
>     E select: [:x x even].
>
>
>                   Is it used in other dialects?
>
> It is used in Squeak:
>
> Context>>runSimulated: aBlock
>      "Simulate the execution of the argument, current. Answer the result it
>     returns."
>
>      ^ thisContext sender
>      runSimulated: aBlock
>      contextAtEachStep: [:ignored]
>
>      "Context runSimulated: [Pen new defaultNib: 5; go: 100]"
>
> See also MCMcdReader>>#loadPatch MCPatch>>#initializeWithBase:target:
There are 24 uses in my image, one from an external package: Xtreams:

CurrentReadOnlySourceFiles cacheDuring: [
  | regex |
  regex := '\[\s*\:\s*\w+\s*\]' asRegex.
  SystemNavigation default browseAllSelect: [ :method |
  regex search: method getSource asString ] ]


>
> I also see two usages in VW, MethodContext>>#selector and BlockContext>>#selector.
> The fact that these two methods still have undescore (left arrow) assignment in source code and have same argument signature [:ignored] speaks for itself!!!
> I'm convinced that it's been an easy hack/feature originating in early 80s (probably by Dan Ingalls), and forgotten since, that never made it into the offical specifications.
> Smalltalk is malleable enough :)
>
> We can deprecate it if we want, but we will have to support backward compatibility in the Parser. The boring side of frozen specs...
> In this case,we'd better not support it in Shout.

Most users just ignore the argument of an error handler block this way,
but that's unnecessary in Squeak, because the block doesn't have to have
any arguments:

  [ self error ] on: Error do: [ "nothing" ]

But some users can't omit the block argument so easily, so perhaps its
worth supporting this construct in Shout.

Levente

>
>                   Levente
>
>                   On Sun, 18 Aug 2019, Nicolas Cellier wrote:
>
>                         Le jeu. 15 août 2019 à 12:21, Levente Uzonyi <[hidden email]> a écrit :
>                              On Thu, 15 Aug 2019, Tobias Pape wrote:
>
>                              >
>                              >> On 15.08.2019, at 03:29, Levente Uzonyi <[hidden email]> wrote:
>                              >>
>                              >> On Wed, 14 Aug 2019, [hidden email] wrote:
>                              >>
>                              >>> A new version of ShoutCore was added to project The Inbox:
>                              >>> http://source.squeak.org/inbox/ShoutCore-ct.69.mcz
>                              >>>
>                              >>> ==================== Summary ====================
>                              >>>
>                              >>> Name: ShoutCore-ct.69
>                              >>> Author: ct
>                              >>> Time: 14 August 2019, 10:43:04.7164 pm
>                              >>> UUID: 7d165f4e-09bf-a445-a664-5e8edb9867b8
>                              >>> Ancestors: ShoutCore-ul.68
>                              >>>
>                              >>> Fix bug in SHParserST80: Wrong styling after blocks with arguments without statements
>                              >>
>                              >> If you mean that Shout should accept [ :x ], then no, I'm pretty sure that's not valid smalltalk syntax, even if Parser accepts it.
>                              >> The vertical bar, even though I consider it unnecessary in all cases, is mandatory when there are arguments.
>                              >
>                              > I only got to know this "shortcut syntax" because eliot used it either Cog or somewhere in trunk when preparing something (Spur? full block closures? I forgot). So this
>                         is a syntax idiosyncrasy that is in active use, not only "old code".
>                              >
>                              > Either we forbid it in the parser and change all of the image or allow it in Shout.
>
>                              Can you give me examples?
>                              I suspect those are just typos, which the parser accidentally accepted
>                              (and Shout as well before my fixes).
>
>                              Levente
>                         I don't remember seeing this syntax before and found it a bit surprising.
>                         So, for the sake of curiosity, I tried in some other dialects.
>                         [:x ] is accepted syntax in
>                         - Visualworks (8.3),
>                         - Pharo (v7 with OpalCompiler)
>                         - Smalltalk-80 (apple v0.?)
>                         [:x ] is invalid in
>                         - Dolphin
>                         - Smalltalk/X (jv branch)
>                         So it seems that it's something originating from original Smalltalk-80, but not reproducted in non derivated dialects...
>                         The bar is mandatory in blue book specification (see the last pages)
>                         Capture d’écran 2019-08-18 à 17.11.53.png
>                         So it seems that implementation did not agree with specifications for ages...
>                         Capture d’écran 2019-08-18 à 18.56.05.png
>
>                              >
>                              > Best regards
>                              >       -Tobias
>                              >
>                              >>
>                              >> Levente
>                              >>
>                              >>>
>                              >>> Thanks Jakob for the report!
>                              >>>
>                              >>> =============== Diff against ShoutCore-ul.68 ===============
>                              >>>
>                              >>> Item was changed:
>                              >>> ----- Method: SHParserST80>>parseBlockArguments (in category 'parse') -----
>                              >>> parseBlockArguments
>                              >>>
>                              >>>     currentTokenFirst == $: ifFalse: [ ^self ].
>                              >>>     [ currentTokenFirst == $: ] whileTrue: [
>                              >>>             self
>                              >>>                     scanPast: #blockArgColon;
>                              >>>                     parseArgument: #blockPatternArg ].
>                              >>> +   ((self parseVerticalBarForTemporaries: #blockArgsBar) and: [
>                              >>> +           currentTokenFirst ~= $] ])
>                              >>> +                   ifFalse: [
>                              >>> +                           self fail ": Missing block args bar" ]!
>                              >>> -   (self parseVerticalBarForTemporaries: #blockArgsBar) ifFalse: [
>                              >>> -           self fail ": Missing block args bar" ]!
>                              >>
>
>
>
>
>
>

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Re: The Inbox: ShoutCore-ct.69.mcz

marcel.taeumel
-1 for supporting [:arg ]

+1 for promoting [:arg | "nothing" ]
+1 for supporting [ "nothing" ] using #cull:

Best,
Marcel

Am 19.08.2019 23:35:56 schrieb Levente Uzonyi <[hidden email]>:

On Mon, 19 Aug 2019, Nicolas Cellier wrote:

>
>
> Le lun. 19 août 2019 à 03:37, John Pfersich via Squeak-dev a écrit :
> The full definition from the draft standards (don’t have the standard handy) is:
> ::= '[' ']'
> ::= [* '|'] [] []
> ::= ':' identifier
>
> The last line is on the next page of the draft.
>
> /————————————————————/For encrypted mail use [hidden email] a free account at ProtonMail.com
> Web: www.objectnets.net and www.objectnets.org
>
> On Aug 18, 2019, at 12:09, JOHN SARKELA via Squeak-dev wrote:
>
> The ANSI standard has the following rules for blocks:
>
> ::= '[' ']'
> ::= [* '|'] [] []
>
> The standard does not recognize [:x] as legal syntax for a block.
>
> Yes, same as blue book. (block temporaries apart, this did not exist in st-80), bar is mandatory.
> On Aug 18, 2019, at 3:03 PM, Levente Uzonyi wrote:
>
> Hi Nicolas,
>
> Thanks for investigating this.
>
> It's been a pretext for playing with historical material ;)
>
> I still think that it's just a parser bug, which is accidentally "used" sometimes, especially because it only works when the block is empty.
>
> Seeing the code, it's the & (hereType ~~ #rightBracket) condition following (t1 size > 0 which makes [:x ] syntax possible.
> Since it has been added explicitely, my bet is that it has been added purposely and deliberataly rather than accidentally.
>
> It seems [:x ] was not accepted in earlier version 00:
>
> [block | blk argNodes argument |
> " '[' {:var.} (:var|statements) ']' BlockNode"
> argNodes ← (Vector new: 1) asStream.
> (self match: #leftBracket)
> ifTrue:
> [[(self match: #colon) and: [((argument ← self match: #word)
> ifTrue: [argNodes next← encoder autoBind: argument]
> ifFalse: [↑self expected: 'Argument name'])]] whileTrueDo: [].
> (argNodes empty or: [(self match: #verticalBar)]) false
> ifTrue: [↑self expected: 'Vertical bar'].
> ((blk ← self statements: argNodes contents doit: false) and: [(self match: #rightBracket)])
> ifTrue: [↑blk].
> ↑self expected: 'Period or right bracket']
> ifFalse: [↑self expected: 'Left bracket']].
> http://xeroxalto.computerhistory.org/Indigo/BasicDisks/Smalltalk14.bfs!1_/.st80sources.v00.html
>
> Or does it work in other dialects with non-empty blocks?
>
>
> Nope, the syntax is only for empty blocks.
> It could have worked for any block if we wanted to, because that vertical bar is just a decoration in blocks.
> From disambiguation POV, it's absolutely unecessary, the block arguments are already delimited by colon prefix :x
> Symetrically, we don't use such delimitation between method pattern and statements... But it evolved across history:
>
> Historically, Smalltalk-76 did use a single (optional) bar for declaring temporaries (if any):
> methodDefnition := pattern [ '|' temporaries ] '[' statements ']'
>
> Then early Smalltalk-80 method definitions did use empty temps systematically '[' pattern '|' '|' statements ']'
> The two bars were mandatory at that time
>
> "374" LADParser$'Parser'
> [temporaries | vars |
> "[ '|' {variable} ] {variable, ..., variable}"
> (self match: #verticalBar) and: [((self match: #verticalBar)
> ifTrue: [↑#()].
> vars ← (Vector new: 8) asStream.
> [hereType #word] whileTrueDo: [vars next← encoder bind: self advance].
> (self match: #verticalBar)
> ifTrue: [↑vars contents])].
> ↑self expected: 'Vertical bar'].
> http://xeroxalto.computerhistory.org/Indigo/BasicDisks/Smalltalk14.bfs!1_/.st80sources.v00.html
>
> I guess that current block syntax is the legacy from all these syntax evolutions/experiments...
>
> Personnally, I like the bar, because it reminds me mathematical notation I learned at school for ensemble comprehension https://fr.wikipedia.org/wiki/Ensemble...
>
>      {x ∊ E | x even }
>
> translated in Smalltalk:
>
>     E select: [:x | x even].
>
> without bar, I'm really NOT used to it:
>     E select: [:x x even].
>
>
> Is it used in other dialects?
>
> It is used in Squeak:
>
> Context>>runSimulated: aBlock
>      "Simulate the execution of the argument, current. Answer the result it
>     returns."
>
>      ^ thisContext sender
>      runSimulated: aBlock
>      contextAtEachStep: [:ignored]
>
>      "Context runSimulated: [Pen new defaultNib: 5; go: 100]"
>
> See also MCMcdReader>>#loadPatch MCPatch>>#initializeWithBase:target:

There are 24 uses in my image, one from an external package: Xtreams:

CurrentReadOnlySourceFiles cacheDuring: [
| regex |
regex := '\[\s*\:\s*\w+\s*\]' asRegex.
SystemNavigation default browseAllSelect: [ :method |
regex search: method getSource asString ] ]


>
> I also see two usages in VW, MethodContext>>#selector and BlockContext>>#selector.
> The fact that these two methods still have undescore (left arrow) assignment in source code and have same argument signature [:ignored] speaks for itself!!!
> I'm convinced that it's been an easy hack/feature originating in early 80s (probably by Dan Ingalls), and forgotten since, that never made it into the offical specifications.
> Smalltalk is malleable enough :)
>
> We can deprecate it if we want, but we will have to support backward compatibility in the Parser. The boring side of frozen specs...
> In this case,we'd better not support it in Shout.

Most users just ignore the argument of an error handler block this way,
but that's unnecessary in Squeak, because the block doesn't have to have
any arguments:

[ self error ] on: Error do: [ "nothing" ]

But some users can't omit the block argument so easily, so perhaps its
worth supporting this construct in Shout.

Levente

>
> Levente
>
> On Sun, 18 Aug 2019, Nicolas Cellier wrote:
>
> Le jeu. 15 août 2019 à 12:21, Levente Uzonyi a écrit :
>      On Thu, 15 Aug 2019, Tobias Pape wrote:
>
>      >
>      >> On 15.08.2019, at 03:29, Levente Uzonyi wrote:
>      >>
>      >> On Wed, 14 Aug 2019, [hidden email] wrote:
>      >>
>      >>> A new version of ShoutCore was added to project The Inbox:
>      >>> http://source.squeak.org/inbox/ShoutCore-ct.69.mcz
>      >>>
>      >>> ==================== Summary ====================
>      >>>
>      >>> Name: ShoutCore-ct.69
>      >>> Author: ct
>      >>> Time: 14 August 2019, 10:43:04.7164 pm
>      >>> UUID: 7d165f4e-09bf-a445-a664-5e8edb9867b8
>      >>> Ancestors: ShoutCore-ul.68
>      >>>
>      >>> Fix bug in SHParserST80: Wrong styling after blocks with arguments without statements
>      >>
>      >> If you mean that Shout should accept [ :x ], then no, I'm pretty sure that's not valid smalltalk syntax, even if Parser accepts it.
>      >> The vertical bar, even though I consider it unnecessary in all cases, is mandatory when there are arguments.
>      >
>      > I only got to know this "shortcut syntax" because eliot used it either Cog or somewhere in trunk when preparing something (Spur? full block closures? I forgot). So this
> is a syntax idiosyncrasy that is in active use, not only "old code".
>      >
>      > Either we forbid it in the parser and change all of the image or allow it in Shout.
>
>      Can you give me examples?
>      I suspect those are just typos, which the parser accidentally accepted
>      (and Shout as well before my fixes).
>
>      Levente
> I don't remember seeing this syntax before and found it a bit surprising.
> So, for the sake of curiosity, I tried in some other dialects.
> [:x ] is accepted syntax in
> - Visualworks (8.3),
> - Pharo (v7 with OpalCompiler)
> - Smalltalk-80 (apple v0.?)
> [:x ] is invalid in
> - Dolphin
> - Smalltalk/X (jv branch)
> So it seems that it's something originating from original Smalltalk-80, but not reproducted in non derivated dialects...
> The bar is mandatory in blue book specification (see the last pages)
> Capture d’écran 2019-08-18 à 17.11.53.png
> So it seems that implementation did not agree with specifications for ages...
> Capture d’écran 2019-08-18 à 18.56.05.png
>
>      >
>      > Best regards
>      >       -Tobias
>      >
>      >>
>      >> Levente
>      >>
>      >>>
>      >>> Thanks Jakob for the report!
>      >>>
>      >>> =============== Diff against ShoutCore-ul.68 ===============
>      >>>
>      >>> Item was changed:
>      >>> ----- Method: SHParserST80>>parseBlockArguments (in category 'parse') -----
>      >>> parseBlockArguments
>      >>>
>      >>>     currentTokenFirst == $: ifFalse: [ ^self ].
>      >>>     [ currentTokenFirst == $: ] whileTrue: [
>      >>>             self
>      >>>                     scanPast: #blockArgColon;
>      >>>                     parseArgument: #blockPatternArg ].
>      >>> +   ((self parseVerticalBarForTemporaries: #blockArgsBar) and: [
>      >>> +           currentTokenFirst ~= $] ])
>      >>> +                   ifFalse: [
>      >>> +                           self fail ": Missing block args bar" ]!
>      >>> -   (self parseVerticalBarForTemporaries: #blockArgsBar) ifFalse: [
>      >>> -           self fail ": Missing block args bar" ]!
>      >>
>
>
>
>
>
>


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[:x] considered improper (was Re: The Inbox: ShoutCore-ct.69.mcz)

timrowledge
In reply to this post by Tobias Pape
At the last SOB meeting we agreed that we would prefer the standard be enforced and that [:x] be considered improper. Make it sew, Mr Tailor...

> On 2019-08-14, at 11:11 PM, Tobias Pape <[hidden email]> wrote:
>
>
>> On 15.08.2019, at 03:29, Levente Uzonyi <[hidden email]> wrote:
>>
>> On Wed, 14 Aug 2019, [hidden email] wrote:
>>
>>> A new version of ShoutCore was added to project The Inbox:
>>> http://source.squeak.org/inbox/ShoutCore-ct.69.mcz
>>>
>>> ==================== Summary ====================
>>>
>>> Name: ShoutCore-ct.69
>>> Author: ct
>>> Time: 14 August 2019, 10:43:04.7164 pm
>>> UUID: 7d165f4e-09bf-a445-a664-5e8edb9867b8
>>> Ancestors: ShoutCore-ul.68
>>>
>>> Fix bug in SHParserST80: Wrong styling after blocks with arguments without statements
>>
>> If you mean that Shout should accept [ :x ], then no, I'm pretty sure that's not valid smalltalk syntax, even if Parser accepts it.
>> The vertical bar, even though I consider it unnecessary in all cases, is mandatory when there are arguments.
>
> I only got to know this "shortcut syntax" because eliot used it either Cog or somewhere in trunk when preparing something (Spur? full block closures? I forgot). So this is a syntax idiosyncrasy that is in active use, not only "old code".
>
> Either we forbid it in the parser and change all of the image or allow it in Shout.
>
> Best regards
> -Tobias
>
>>
>> Levente
>>
>>>
>>> Thanks Jakob for the report!
>>>
>>> =============== Diff against ShoutCore-ul.68 ===============
>>>
>>> Item was changed:
>>> ----- Method: SHParserST80>>parseBlockArguments (in category 'parse') -----
>>> parseBlockArguments
>>>
>>> currentTokenFirst == $: ifFalse: [ ^self ].
>>> [ currentTokenFirst == $: ] whileTrue: [
>>> self
>>> scanPast: #blockArgColon;
>>> parseArgument: #blockPatternArg ].
>>> + ((self parseVerticalBarForTemporaries: #blockArgsBar) and: [
>>> + currentTokenFirst ~= $] ])
>>> + ifFalse: [
>>> + self fail ": Missing block args bar" ]!
>>> - (self parseVerticalBarForTemporaries: #blockArgsBar) ifFalse: [
>>> - self fail ": Missing block args bar" ]!
>>
>
>
>
>


tim
--
tim Rowledge; [hidden email]; http://www.rowledge.org/tim
Strange OpCodes: IO: Illogical Or



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Re: [:x] considered improper (was Re: The Inbox: ShoutCore-ct.69.mcz)

Christoph Thiede
Sorry for reviving this old thread ...

This is still an open issue, isn't it?  (oh, it would be so comfortable if
we had something like GitHub issues ...)


And just one related question: According to the BNF John mentioned --

(from the  ANSI Smaltalk Standard
<https://wiki.squeak.org/squeak/uploads/172/standard_v1_9-indexed.pdf#page=21,22>
)
 -- the following should be valid syntax as well, shouldn't it?



The explanation is that, according to Wikipedia, an asterisk in the BNF
stands for "0 or more times". So provided that there is not a mistake in the
official standard document, shouldn't we support the above example?

Which is the exact standard we are following? The Blue Book? The ANSI
Smalltalk Standard?

Best,
Christoph



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Re: [:x] considered improper (was Re: The Inbox: ShoutCore-ct.69.mcz)

Christoph Thiede

[Ugh, Nabble removed all my code examples again. Resend below:]



Von: Squeak-dev <[hidden email]> im Auftrag von Thiede, Christoph
Gesendet: Montag, 10. Februar 2020 14:10 Uhr
An: [hidden email]
Betreff: Re: [squeak-dev] [:x] considered improper (was Re: The Inbox: ShoutCore-ct.69.mcz)
 
Sorry for reviving this old thread ...

This is still an open issue, isn't it?  (oh, it would be so comfortable if we had something like GitHub issues ...)


And just one related question: According to the BNF John mentioned --
<block constructor> ::= '[' <block body> ']'
<block body> ::= [<block argument>* '|'] [<temporaries>] [<statements>]
<block argument> ::= ':' identifier
(from the ANSI Smaltalk Standard)
 -- the following should be valid syntax as well, shouldn't it?

[|] value.

The explanation is that, according to Wikipedia, an asterisk in the BNF stands for "0 or more times". So provided that there is not a mistake in the official standard document, shouldn't we support the above example?

Which is the exact standard we are following? The Blue Book? The ANSI Smalltalk Standard?

Best,
Christoph





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Re: [:x] considered improper (was Re: The Inbox: ShoutCore-ct.69.mcz)

Levente Uzonyi
Hi Christoph,

My understanding is that the conclusion was that [:x] should not be
valid[1].
In my option, it makes no sense to support a useless extremal case.
The BNF you posted below says that it is not valid.

But the BNF is from the ANSI standard's draft, so there's an extremely
slim chance that it was changed in the actual standard. But
- I doubt anyone would like to pay for it to find out
- I'm not aware of any smalltalk implementation that would strictly follow
the standard
- the standard is not a good standard

In my option, [|] is another extremal case that I don't think we need to
support.
It's longer than [], and both parsers detect it the same way: the closing
| of the temporary declaration is missing.

So, to sum it up, IMHO neither [:x], [:x :y] nor [|] should be supported.
Parser accepts [:x] and [:x :y], which should be fixed; perhaps just a
warning should be raised.


Levente

[1] http://forum.world.st/The-Inbox-ShoutCore-ct-69-mcz-tp5102398p5102912.html
On Mon, 10 Feb 2020, Thiede, Christoph wrote:

>
> [Ugh, Nabble removed all my code examples again. Resend below:]
>
>
> _________________________________________________________________________________________________________________________________________________________________________________________________________________________________
> Von: Squeak-dev <[hidden email]> im Auftrag von Thiede, Christoph
> Gesendet: Montag, 10. Februar 2020 14:10 Uhr
> An: [hidden email]
> Betreff: Re: [squeak-dev] [:x] considered improper (was Re: The Inbox: ShoutCore-ct.69.mcz)  
> Sorry for reviving this old thread ...
>
> This is still an open issue, isn't it?  (oh, it would be so comfortable if we had something like GitHub issues ...)
>
>
> And just one related question: According to the BNF John mentioned --
>
> <block constructor> ::= '[' <block body> ']'
> <block body> ::= [<block argument>* '|'] [<temporaries>] [<statements>]
> <block argument> ::= ':' identifier
> (from the ANSI Smaltalk Standard)
>  -- the following should be valid syntax as well, shouldn't it?
>
> [|] value.
>
> The explanation is that, according to Wikipedia, an asterisk in the BNF stands for "0 or more times". So provided that there is not a mistake in the official standard document, shouldn't we support the above example?
>
> Which is the exact standard we are following? The Blue Book? The ANSI Smalltalk Standard?
>
> Best,
> Christoph
>
>
>
>
>
> --
> Sent from: http://forum.world.st/Squeak-Dev-f45488.html
>
>
>

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Re: [:x] considered improper (was Re: The Inbox: ShoutCore-ct.69.mcz)

Christoph Thiede

Hi Levente,


alright, I like your arguments (sorry for the bad joke)! I would also not like to support [|] unless it's necessary.


How do you feel about Compiler-ct.417? Another, more expensive approach might be a SyntaxDeprecationWarning. :-)


Best,

Christoph


Von: Squeak-dev <[hidden email]> im Auftrag von Levente Uzonyi <[hidden email]>
Gesendet: Montag, 10. Februar 2020 22:46:42
An: The general-purpose Squeak developers list
Betreff: Re: [squeak-dev] [:x] considered improper (was Re: The Inbox: ShoutCore-ct.69.mcz)
 
Hi Christoph,

My understanding is that the conclusion was that [:x] should not be
valid[1].
In my option, it makes no sense to support a useless extremal case.
The BNF you posted below says that it is not valid.

But the BNF is from the ANSI standard's draft, so there's an extremely
slim chance that it was changed in the actual standard. But
- I doubt anyone would like to pay for it to find out
- I'm not aware of any smalltalk implementation that would strictly follow
the standard
- the standard is not a good standard

In my option, [|] is another extremal case that I don't think we need to
support.
It's longer than [], and both parsers detect it the same way: the closing
| of the temporary declaration is missing.

So, to sum it up, IMHO neither [:x], [:x :y] nor [|] should be supported.
Parser accepts [:x] and [:x :y], which should be fixed; perhaps just a
warning should be raised.


Levente

[1] http://forum.world.st/The-Inbox-ShoutCore-ct-69-mcz-tp5102398p5102912.html
On Mon, 10 Feb 2020, Thiede, Christoph wrote:

>
> [Ugh, Nabble removed all my code examples again. Resend below:]
>
>
> _________________________________________________________________________________________________________________________________________________________________________________________________________________________________
> Von: Squeak-dev <[hidden email]> im Auftrag von Thiede, Christoph
> Gesendet: Montag, 10. Februar 2020 14:10 Uhr
> An: [hidden email]
> Betreff: Re: [squeak-dev] [:x] considered improper (was Re: The Inbox: ShoutCore-ct.69.mcz)  
> Sorry for reviving this old thread ...
>
> This is still an open issue, isn't it?  (oh, it would be so comfortable if we had something like GitHub issues ...)
>
>
> And just one related question: According to the BNF John mentioned --
>
> <block constructor> ::= '[' <block body> ']'
> <block body> ::= [<block argument>* '|'] [<temporaries>] [<statements>]
> <block argument> ::= ':' identifier
> (from the ANSI Smaltalk Standard)
>  -- the following should be valid syntax as well, shouldn't it?
>
> [|] value.
>
> The explanation is that, according to Wikipedia, an asterisk in the BNF stands for "0 or more times". So provided that there is not a mistake in the official standard document, shouldn't we support the above example?
>
> Which is the exact standard we are following? The Blue Book? The ANSI Smalltalk Standard?
>
> Best,
> Christoph
>
>
>
>
>
> --
> Sent from: http://forum.world.st/Squeak-Dev-f45488.html
>
>
>


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Re: [:x] considered improper (was Re: The Inbox: ShoutCore-ct.69.mcz)

Squeak - Dev mailing list
In reply to this post by Levente Uzonyi
I did pay for the standard and AFAICT there were no changes between the last draft and the issued standard. In my opinion, the standard is good as far as it went, which wasn’t too far. That’s why various Smalltalk implementations vary so much, as Christoph has found. 

It can be a nontrivial task to port extensions from one dialect to another, even those derived from Squeak. Some dialects even claim they’re not even Smalltalk.

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On Feb 10, 2020, at 13:46, Levente Uzonyi <[hidden email]> wrote:

Hi Christoph,

My understanding is that the conclusion was that [:x] should not be valid[1].
In my option, it makes no sense to support a useless extremal case.
The BNF you posted below says that it is not valid.

But the BNF is from the ANSI standard's draft, so there's an extremely slim chance that it was changed in the actual standard. But
- I doubt anyone would like to pay for it to find out
- I'm not aware of any smalltalk implementation that would strictly follow the standard
- the standard is not a good standard

In my option, [|] is another extremal case that I don't think we need to support.
It's longer than [], and both parsers detect it the same way: the closing | of the temporary declaration is missing.

So, to sum it up, IMHO neither [:x], [:x :y] nor [|] should be supported. Parser accepts [:x] and [:x :y], which should be fixed; perhaps just a warning should be raised.


Levente

[1] http://forum.world.st/The-Inbox-ShoutCore-ct-69-mcz-tp5102398p5102912.html
On Mon, 10 Feb 2020, Thiede, Christoph wrote:

[Ugh, Nabble removed all my code examples again. Resend below:]
_________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Von: Squeak-dev <[hidden email]> im Auftrag von Thiede, Christoph
Gesendet: Montag, 10. Februar 2020 14:10 Uhr
An: [hidden email]
Betreff: Re: [squeak-dev] [:x] considered improper (was Re: The Inbox: ShoutCore-ct.69.mcz)  
Sorry for reviving this old thread ...
This is still an open issue, isn't it?  (oh, it would be so comfortable if we had something like GitHub issues ...)
And just one related question: According to the BNF John mentioned --
<block constructor> ::= '[' <block body> ']'
<block body> ::= [<block argument>* '|'] [<temporaries>] [<statements>]
<block argument> ::= ':' identifier
(from the ANSI Smaltalk Standard)
 -- the following should be valid syntax as well, shouldn't it?
[|] value.
The explanation is that, according to Wikipedia, an asterisk in the BNF stands for "0 or more times". So provided that there is not a mistake in the official standard document, shouldn't we support the above example?
Which is the exact standard we are following? The Blue Book? The ANSI Smalltalk Standard?
Best,
Christoph
--
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Re: [:x] considered improper (was Re: The Inbox: ShoutCore-ct.69.mcz)

Christoph Thiede

Just to be sure: So you vote for [|] being valid Smalltalk syntax? :)


Von: Squeak-dev <[hidden email]> im Auftrag von John Pfersich via Squeak-dev <[hidden email]>
Gesendet: Dienstag, 11. Februar 2020 10:28:00
An: The general-purpose Squeak developers list
Betreff: Re: [squeak-dev] [:x] considered improper (was Re: The Inbox: ShoutCore-ct.69.mcz)
 
I did pay for the standard and AFAICT there were no changes between the last draft and the issued standard. In my opinion, the standard is good as far as it went, which wasn’t too far. That’s why various Smalltalk implementations vary so much, as Christoph has found. 

It can be a nontrivial task to port extensions from one dialect to another, even those derived from Squeak. Some dialects even claim they’re not even Smalltalk.

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On Feb 10, 2020, at 13:46, Levente Uzonyi <[hidden email]> wrote:

Hi Christoph,

My understanding is that the conclusion was that [:x] should not be valid[1].
In my option, it makes no sense to support a useless extremal case.
The BNF you posted below says that it is not valid.

But the BNF is from the ANSI standard's draft, so there's an extremely slim chance that it was changed in the actual standard. But
- I doubt anyone would like to pay for it to find out
- I'm not aware of any smalltalk implementation that would strictly follow the standard
- the standard is not a good standard

In my option, [|] is another extremal case that I don't think we need to support.
It's longer than [], and both parsers detect it the same way: the closing | of the temporary declaration is missing.

So, to sum it up, IMHO neither [:x], [:x :y] nor [|] should be supported. Parser accepts [:x] and [:x :y], which should be fixed; perhaps just a warning should be raised.


Levente

[1] http://forum.world.st/The-Inbox-ShoutCore-ct-69-mcz-tp5102398p5102912.html
On Mon, 10 Feb 2020, Thiede, Christoph wrote:

[Ugh, Nabble removed all my code examples again. Resend below:]
_________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Von: Squeak-dev <[hidden email]> im Auftrag von Thiede, Christoph
Gesendet: Montag, 10. Februar 2020 14:10 Uhr
An: [hidden email]
Betreff: Re: [squeak-dev] [:x] considered improper (was Re: The Inbox: ShoutCore-ct.69.mcz)  
Sorry for reviving this old thread ...
This is still an open issue, isn't it?  (oh, it would be so comfortable if we had something like GitHub issues ...)
And just one related question: According to the BNF John mentioned --
<block constructor> ::= '[' <block body> ']'
<block body> ::= [<block argument>* '|'] [<temporaries>] [<statements>]
<block argument> ::= ':' identifier
(from the ANSI Smaltalk Standard)
 -- the following should be valid syntax as well, shouldn't it?
[|] value.
The explanation is that, according to Wikipedia, an asterisk in the BNF stands for "0 or more times". So provided that there is not a mistake in the official standard document, shouldn't we support the above example?
Which is the exact standard we are following? The Blue Book? The ANSI Smalltalk Standard?
Best,
Christoph
--
Sent from: http://forum.world.st/Squeak-Dev-f45488.html



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Re: [:x] considered improper (was Re: The Inbox: ShoutCore-ct.69.mcz)

Squeak - Dev mailing list
In reply to this post by Christoph Thiede
Btw the standard uses a modified EBNF to describe the productions. That’s explained in the first part of the standard. Everything cascades in the standard, so you really need to commit to reading the whole standard, not the Wikipedia article. It’s a pain, but I’ve found it useful to do so. But then I’ve been a computer geek for 48 years, and this type of stuff is what I get paid to do. So nitpicking is my job.

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On Feb 10, 2020, at 14:41, Thiede, Christoph <[hidden email]> wrote:

> The explanation is that, according to Wikipedia, an asterisk in the BNF stands for "0 or more times". So provided that there is not a mistake in the official standard document, shouldn't we support the above example?


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