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is there an easy way to know the SmallInteger instances?

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Mariano Martinez Peck

is there an easy way to know the SmallInteger instances?

If I do SmallInteger alIInstances I get an empty array, and of course, with SmallInteger instanceCount I get zero.

Now, I can understand that from the VM point of view, but for the final user, this should be polymorphic. For example, for instanceCount, I would like to know all the "variable slots" that has a 1 in the last bit.
Is this already possible? if true, which message? if not, should I hack in the vm and code a primitive that does this?

And the same for allInstances, if I can inspect 5, I should be also to inspect SmallInteger allInstances, and SmallInteger allInstances first, etc....

thanks

Mariano

Schwab,Wilhelm K

Re: is there an easy way to know the SmallInteger instances?

Mariano,

I see your point, but given the immediate object encoding tricks I'm not sure it's possible. Would the class methods #minVal and #maxVal be of any use to you?

Bill

________________________________________
From: [hidden email] [[hidden email]] On Behalf Of Mariano Martinez Peck [[hidden email]]
Sent: Sunday, November 21, 2010 4:41 PM
To: Pharo Development
Subject: [Pharo-project] is there an easy way to know the SmallInteger instances?

If I do SmallInteger alIInstances I get an empty array, and of course, with SmallInteger instanceCount I get zero.

Now, I can understand that from the VM point of view, but for the final user, this should be polymorphic. For example, for instanceCount, I would like to know all the "variable slots" that has a 1 in the last bit.
Is this already possible? if true, which message? if not, should I hack in the vm and code a primitive that does this?

And the same for allInstances, if I can inspect 5, I should be also to inspect SmallInteger allInstances, and SmallInteger allInstances first, etc....

thanks

Mariano

Mariano Martinez Peck

Re: is there an easy way to know the SmallInteger instances?

On Sun, Nov 21, 2010 at 11:55 PM, Schwab,Wilhelm K <[hidden email]> wrote:

Mariano,

I see your point, but given the immediate object encoding tricks I'm not sure it's possible.

:( It's a pity. Because most users should not be aware of this. This should be completly transparent for the developer.

Would the class methods #minVal and #maxVal be of any use to you?

No :( Maybe it is better in this way: I want to know how many instances/temp var have a SmallInetger. This means, how many slots/words have a 1 in the last bit. This is what I understand by "Smallinteger instances".

Bill

________________________________________
From: [hidden email] [[hidden email]] On Behalf Of Mariano Martinez Peck [[hidden email]]
Sent: Sunday, November 21, 2010 4:41 PM
To: Pharo Development
Subject: [Pharo-project] is there an easy way to know the SmallInteger instances?

If I do SmallInteger alIInstances I get an empty array, and of course, with SmallInteger instanceCount I get zero.

Now, I can understand that from the VM point of view, but for the final user, this should be polymorphic. For example, for instanceCount, I would like to know all the "variable slots" that has a 1 in the last bit.
Is this already possible? if true, which message? if not, should I hack in the vm and code a primitive that does this?

And the same for allInstances, if I can inspect 5, I should be also to inspect SmallInteger allInstances, and SmallInteger allInstances first, etc....

thanks

Mariano

Eliot Miranda-2

Re: is there an easy way to know the SmallInteger instances?

On Sun, Nov 21, 2010 at 2:59 PM, Mariano Martinez Peck <[hidden email]> wrote:

On Sun, Nov 21, 2010 at 11:55 PM, Schwab,Wilhelm K <[hidden email]> wrote:

Mariano,

I see your point, but given the immediate object encoding tricks I'm not sure it's possible.

:( It's a pity. Because most users should not be aware of this. This should be completly transparent for the developer.

Would the class methods #minVal and #maxVal be of any use to you?

No :( Maybe it is better in this way: I want to know how many instances/temp var have a SmallInetger. This means, how many slots/words have a 1 in the last bit. This is what I understand by "Smallinteger instances".

That's the number of references to SmallInteger. If all those slots contain references to 0 then they're still referring to a single object. The number of instances of SmallInteger is SmallInteger maxVal - SmallInteger minVal + 1, period. But they're virtual objects so they don't take any space; only their references take space. (IMO)

So you could implement

SmallInteger class>>instanceCount

^self maxVal - self minVal + 1

SmallInteger class>>allInstances

^self minVal to: self maxVal

you could implement the following but it's of academic interest only; it'll take a long time on a 64-bit implementation ;) If you add this then you have to guard against it being invoked because shure as s**t someone will wonder why the system isn't doing anything when they ask some apparently reasonable question about instance counts...

SmallInteger class>>allInstancesDo: aBlock

self minVal to: self maxVal do: aBlock

best

Eliot

Bill

________________________________________
From: [hidden email] [[hidden email]] On Behalf Of Mariano Martinez Peck [[hidden email]]
Sent: Sunday, November 21, 2010 4:41 PM
To: Pharo Development
Subject: [Pharo-project] is there an easy way to know the SmallInteger instances?

If I do SmallInteger alIInstances I get an empty array, and of course, with SmallInteger instanceCount I get zero.

Now, I can understand that from the VM point of view, but for the final user, this should be polymorphic. For example, for instanceCount, I would like to know all the "variable slots" that has a 1 in the last bit.
Is this already possible? if true, which message? if not, should I hack in the vm and code a primitive that does this?

And the same for allInstances, if I can inspect 5, I should be also to inspect SmallInteger allInstances, and SmallInteger allInstances first, etc....

thanks

Mariano

Mariano Martinez Peck

Re: is there an easy way to know the SmallInteger instances?

On Mon, Nov 22, 2010 at 12:10 AM, Eliot Miranda <[hidden email]> wrote:

On Sun, Nov 21, 2010 at 2:59 PM, Mariano Martinez Peck <[hidden email]> wrote:

On Sun, Nov 21, 2010 at 11:55 PM, Schwab,Wilhelm K <[hidden email]> wrote:

Mariano,

I see your point, but given the immediate object encoding tricks I'm not sure it's possible.

:( It's a pity. Because most users should not be aware of this. This should be completly transparent for the developer.

Would the class methods #minVal and #maxVal be of any use to you?

No :( Maybe it is better in this way: I want to know how many instances/temp var have a SmallInetger. This means, how many slots/words have a 1 in the last bit. This is what I understand by "Smallinteger instances".

That's the number of references to SmallInteger.

ok...and how can I know this then? ;)

If all those slots contain references to 0 then they're still referring to a single object. The number of instances of SmallInteger is SmallInteger maxVal - SmallInteger minVal + 1, period.

isn't that all the MAX possible instances??? If in my whole image, I never use the number 42, why would you count it?

But they're virtual objects so they don't take any space; only their references take space. (IMO)

Ok, at least we agree it cannot be zero. At least it is not clear from a normal developer that doesnt know anything about the VM.

So you could implement
SmallInteger class>>instanceCount
   ^self maxVal - self minVal + 1

SmallInteger class>>allInstances

   ^self minVal to: self maxVal

you could implement the following but it's of academic interest only; it'll take a long time on a 64-bit implementation ;) If you add this then you have to guard against it being invoked because shure as s**t someone will wonder why the system isn't doing anything when they ask some apparently reasonable question about instance counts...

SmallInteger class>>allInstancesDo: aBlock
   self minVal to: self maxVal do: aBlock

best
Eliot

Bill

________________________________________
From: [hidden email] [[hidden email]] On Behalf Of Mariano Martinez Peck [[hidden email]]
Sent: Sunday, November 21, 2010 4:41 PM
To: Pharo Development
Subject: [Pharo-project] is there an easy way to know the SmallInteger instances?

If I do SmallInteger alIInstances I get an empty array, and of course, with SmallInteger instanceCount I get zero.

Now, I can understand that from the VM point of view, but for the final user, this should be polymorphic. For example, for instanceCount, I would like to know all the "variable slots" that has a 1 in the last bit.
Is this already possible? if true, which message? if not, should I hack in the vm and code a primitive that does this?

And the same for allInstances, if I can inspect 5, I should be also to inspect SmallInteger allInstances, and SmallInteger allInstances first, etc....

thanks

Mariano

Schwab,Wilhelm K

Re: is there an easy way to know the SmallInteger instances?

In reply to this post by Eliot Miranda-2

But by iterating over all small integers, are you not "instantiating" ones that were not in use? Dr. Heisenberg will get a good grin out this one :)

________________________________________
From: [hidden email] [[hidden email]] On Behalf Of Eliot Miranda [[hidden email]]
Sent: Sunday, November 21, 2010 6:10 PM
To: [hidden email]
Subject: Re: [Pharo-project] is there an easy way to know the SmallInteger instances?

So you could implement
SmallInteger class>>instanceCount
^self maxVal - self minVal + 1

SmallInteger class>>allInstances
^self minVal to: self maxVal

you could implement the following but it's of academic interest only; it'll take a long time on a 64-bit implementation ;) If you add this then you have to guard against it being invoked because shure as s**t someone will wonder why the system isn't doing anything when they ask some apparently reasonable question about instance counts...

SmallInteger class>>allInstancesDo: aBlock
self minVal to: self maxVal do: aBlock

best
Eliot

csrabak

Re: is there an easy way to know the SmallInteger instances?

In reply to this post by Mariano Martinez Peck

Mariano,

Your post has made think. . . for the final user this would put this method farther from OO as possible, wouldn't it?

Mariano Martinez Peck

Re: is there an easy way to know the SmallInteger instances?

On Tue, Nov 23, 2010 at 8:18 PM, <[hidden email]> wrote:

Mariano,

Your post has made think. . . for the final user this would put this method farther from OO as possible, wouldn't it?

which method and why ? ;)

Peter van Rooijen

Re: is there an easy way to know the SmallInteger instances?

In reply to this post by Mariano Martinez Peck

Mariano,

SmallIntegers don't really exist as objects.

The compiler/vm only make you think they exist.

In fact they are encoded in the object pointer.

Perhaps you knew this already.

As to the other question, how many variables

hold a SmallInteger, you cannot really calculate

that for temp vars, although you could get a good

stab at it if you are determined.

For instance variables, you collect all objects

in the image in a collection, then for each element

you enumerate from 1 to the number of named instvars

using x class instSize and instVarAt:

and also the indexed inst vars

using basicSize and basicAt:

and each time you test if the class

is SmallInteger and if so you increment

a counter

Does that help?

Cheers, Peter

On Mon, 22 Nov 2010 00:48:03 +0100, Mariano Martinez Peck <[hidden email]> wrote:

On Mon, Nov 22, 2010 at 12:10 AM, Eliot Miranda <[hidden email]> wrote:

On Sun, Nov 21, 2010 at 2:59 PM, Mariano Martinez Peck <[hidden email]> wrote:

On Sun, Nov 21, 2010 at 11:55 PM, Schwab,Wilhelm K <[hidden email]> wrote:

Mariano,

I see your point, but given the immediate object encoding tricks I'm not sure it's possible.

:(   It's a pity. Because most users should not be aware of this. This should be completly transparent for the developer.

Would the class methods #minVal and #maxVal be of any use to you?

No :( Maybe it is better in this way: I want to know how many instances/temp var have a SmallInetger. This means, how many slots/words have a 1 in the last bit. This is what I understand by "Smallinteger instances".

That's the number of references to SmallInteger.

ok...and how can I know this then? ;)

If all those slots contain references to 0 then they're still referring to a single object. The number of instances of SmallInteger is SmallInteger maxVal - SmallInteger minVal + 1, period.

isn't that all the MAX possible instances??? If in my whole image, I never use the number 42, why would you count it?

But they're virtual objects so they don't take any space; only their references take space. (IMO)

Ok, at least we agree it cannot be zero. At least it is not clear from a normal developer that doesnt know anything about the VM.

So you could implement
SmallInteger class>>instanceCount
   ^self maxVal - self minVal + 1

SmallInteger class>>allInstances

   ^self minVal to: self maxVal

you could implement the following but it's of academic interest only; it'll take a long time on a 64-bit implementation ;) If you add this then you have to guard against it being invoked because shure as s**t someone will wonder why the system isn't doing anything when they ask some apparently reasonable question about instance counts...

SmallInteger class>>allInstancesDo: aBlock
   self minVal to: self maxVal do: aBlock

best
Eliot

Bill

________________________________________
From: [hidden email] [[hidden email]] On Behalf Of Mariano Martinez Peck [[hidden email]]
Sent: Sunday, November 21, 2010 4:41 PM
To: Pharo Development
Subject: [Pharo-project] is there an easy way to know the SmallInteger instances?

If I do SmallInteger alIInstances I get an empty array, and of course, with SmallInteger instanceCount I get zero.

Now, I can understand that from the VM point of view, but for the final user, this should be polymorphic. For example, for instanceCount, I would like to know all the "variable slots" that has a 1 in the last bit.
Is this already possible? if true, which message? if not, should I hack in the vm and code a primitive that does this?

And the same for allInstances, if I can inspect 5, I should be also to inspect SmallInteger allInstances, and SmallInteger allInstances first, etc....

thanks

Mariano

Peter van Rooijen
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5152 VJ Drunen
m: 06-2854 2048