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Smalltalk = strongly typed
by btc＠openinworld.com Aug. 5, 2013

Aug. 5, 2013

greetings all, I'm in the final weeks of writing up my Masters dissertation and seeking some scholarly references to Smalltalk being "Strongly Typed." I my review of Smalltalk I was surprised to find that [1] describes Smalltalk as Strongly Typed, since Smalltalk is sometimes denigrated as being untyped / weakly typed. From reviewing discussion forums this now makes sense, but I can only find one of scholarly reference that briefly mentions this [2]. The most enlightening is [3] which defines Type Strength as: "A strongly typed language prevents any operation on the wrong type of data. In weakly typed languages there are ways to escape this restriction: type conversions" meaning that getting a MNU is a form of Strong Typing since you can't make a Smalltalk object run a method that is not its own. The problem appears to be that Strong Typing has been synonymous with Static Typing for a long time, and Static Typing strongly ties types to variables, except in Dynamically Typed languages, I think types can be considered independently from variables, in which case the definition of [3] has some merit, hence Smalltalk is Strongly Typed. Sounds controversial, so I'm just hoping for some peer reviewed backup - but only you have something easily to hand. This is just a small thing I can just leave out if necessary. cheers -ben [1] http://www.squeak.org/Features/ [2] p15, http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.35.7507&rep=rep1&t… [3] http://www.cs.kuleuven.ac.be/publicaties/rapporten/cw/CW415.pdf

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Announcer problem :)
by StÃ©phane Ducasse Aug. 4, 2013

Aug. 4, 2013

addDependent: anObject self announcer on: MorphChanged do: [ :ann | anObject update: ann selector ]. self announcer on: MorphChangedWithArguments do: [ :ann | anObject update: ann selector with: ann arguments ]. ^ anObject is an example of the problem because addDependent: was holding also weakly its dependent and now we cannot use weak with blocks. Stef

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about on:do: and weak
by StÃ©phane Ducasse Aug. 4, 2013

Aug. 4, 2013

Hi guys we are looking at the memory leak problems with igor and here are the conclusions: we are renaming on:do: for shortcut into onKey:do: so that we can see a bit more (normally easy) Now the complex part. on:do: should not be used in weak announcement. because the block holds a context that prevents the garbage collection to reclaim the object. For blocks implicitly the receiver of the message containing the block is held strongly. Now the block cannot We are adding a message in the on:do: implementation and we will have a look at the complete image. on:do: should only be used for strong references. The problem is that for UI we need weak. So we are looking at users for now. Stef

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New version of PharoSound
by StÃ©phane Ducasse Aug. 4, 2013

Aug. 4, 2013

Hi I merged Jannik clean and I commited a new version of the configuration. Now it works on Pharo 20 and also on Pharo 30 And I will produce a new System-Sound for the kernel based on Pavel work and I will produce a new configuration. Stef

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DigitalSignatureAlgorithm depends on Sound
by StÃ©phane Ducasse Aug. 3, 2013

Aug. 3, 2013

Hi I discovered that UUIDGenerator and DigitalSignatureAlgorithm used in some encrypting algo are dependent of Sound. BaseSoundSystem>>:randomBitsFromSoundInput: bitCount "Answer a positive integer with the given number of random bits of 'noise' from a sound input source. Typically, one would use a microphone or line input as the sound source, although many sound cards have enough thermal noise that you get random low-order sample bits even with no microphone connected. Only the least signficant bit of the samples is used. Since not all sound cards support 16-bits of sample resolution, we use the lowest bit that changes." "(1 to: 10) collect: [:i | BaseSoundSystem new randomBitsFromSoundInput: 512]" | recorder buf mid samples bitMask randomBits bit | "collect some sound data" recorder := SoundRecorder new clearRecordedSound. recorder resumeRecording. (Delay forSeconds: 1) wait. recorder stopRecording. buf := recorder condensedSamples. "grab bitCount samples from the middle" mid := buf monoSampleCount // 2. samples := buf copyFrom: mid to: mid + bitCount - 1. "find the least significant bit that varies" bitMask := 1. [bitMask < 16r10000 and: [(samples collect: [:s | s bitAnd: bitMask]) asSet size < 2]] whileTrue: [bitMask := bitMask bitShift: 1]. bitMask = 16r10000 ifTrue: [^ self error: 'sound samples do not vary']. "pack the random bits into a positive integer" randomBits := 0. 1 to: samples size do: [:i | bit := ((samples at: i) bitAnd: bitMask) = 0 ifTrue: [0] ifFalse: [1]. randomBits := (randomBits bitShift: 1) + bit]. ^ randomBits Now I was thinking that when the sound package is not loaded we could have a random number generator. Stef

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Discard option while editing code seems to be broken or strange
by StÃ©phane Ducasse Aug. 3, 2013

Aug. 3, 2013

When I modify a method and click on somewhere else I get a pop up and pressing discard does not work but pops up another. Now I'm trying to reproduce the problem to describe it clearly and I cannot anymore but I'm sure I did get this strange behavior. Stef

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SimpleMIDIPort midiIsSupported returns the first time false and after all the time true :)
by StÃ©phane Ducasse Aug. 3, 2013

Aug. 3, 2013

Strange May be the logic in the primitive is strange. midiIsSupported "Answer true if this platform supports MIDI." ^ self primPortCount > 0 primPortCount "Answer the number of MIDI ports supported by this platform, or zero if this primitive is not implemented." <primitive: 'primitiveMIDIGetPortCount' module: 'MIDIPlugin'> ^ 0 Stef

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Aug. 3, 2013

Because when I merge and I click on apply the change is not applied in the image (when I do not accept the button in the merge tool)? Stef

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Still broken Date comparaison in 2.0?
by hilaire Aug. 3, 2013

Aug. 3, 2013

Instances value from stacking GrowlMorphs: TimeStamp now -> 4 August 2013 1:18:30 am vanishTime -> 4 August 2013 12:51:51.62 am TimeStamp now < vanishTime ->true Inspectors: <http://forum.world.st/file/n4702023/TimesStampInspectors.png> Hilaire -- View this message in context: http://forum.world.st/Still-broken-Date-comparaison-in-2-0-tp4702023.html Sent from the Pharo Smalltalk Developers mailing list archive at Nabble.com.

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Aug. 3, 2013

Hi guys I wonder what we can do about AppRegistry I imagine that we can remove MailSender. I'm going over the code on the image as well as http://code.google.com/p/pharo/issues/detail?id=6996 and pavel changes. Any feedback is welcome. Stef

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