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Koos Brandt

Question

I am still learning but something weird happened.

In a new Workspace

Do-it myVar := LargeInteger new

Print-it myVar <error in printString: try 'Inspect it' to debug>

When I inspect it I get

SubclassResponsibility: LargeInteger had the subclass responsibility to implement #printOn:base:

When I browse LargeInteger, then at Integer level I get a message “new” as follows:

new

self == Integer ifTrue: [

^ self error: 'Integer is an abstract class. Make a concrete subclass.'].

^ super new

I looked for new higher up in the hierarchy(super), but could not see it. Maybe I am a bit dumb still with looking up.

I tried on SmallInteger a new, but got back

Error: SmallIntegers can only be created by performing arithmetic.

I then checked and noticed that SmallInteger actually have new and basicNew implemented (override)

So the error I got on smallinteger was from the override

LargeInteger has no override, but has a “silent" error

This seems a bit weird to me

Just so you know I also tried

Do-it myVar := LargeInteger new: 10000

Print-it myVar class. -> LargeInteger

Dot-it myVar := myVar + 1

The last statement hangs the image! (Tried 3 times)

Comment:

1. I am surprised that Do-it did not give me an error on the new: (there is a message is the hierarchy of new:neg and maybe the neg is optional?)

2. The new: seemed to have created 10000 LargeIntegers

3. I tried the new: also with just 5, and same result, image hang. (I thought 10,000 was maybe a very large loop for the + 1..)

Did I damage something in the image maybe? I started this one just yesterday to look at MOOC week1.

I do not need LargeIntegers for now but …

This is Pharo 6.0 64 Bit on Mac OSX Sierra 10.12.5 (iMac 27, 2.9GHz Intel Core i5, 16GB RAM)

Regards

Koos Brandt

0824542028

philippeback

Re: Question

LargeInteger is not what you should use.

Try this:

v:= SmallInteger minVal - 1

In 64-bit, one gets:"-1152921504606846977"

and there you have a LargeNegativeInteger that prints properly.

v := SmallInteger maxval + 1

"1152921504606846976"

same but positive.

You have Integers that are Numbers and why bother with the large or small thing? It works.

If things are getting slow, well, profile and optimize.

Phil

On Mon, Jul 24, 2017 at 10:54 AM, Koos Brandt <[hidden email]> wrote:

Hi

I am still learning but something weird happened.

In a new Workspace

Do-it myVar := LargeInteger new
Print-it myVar <error in printString: try 'Inspect it' to debug>

When I inspect it I get
SubclassResponsibility: LargeInteger had the subclass responsibility to implement #printOn:base:

When I browse LargeInteger, then at Integer level I get a message “new” as follows:

new

self == Integer ifTrue: [
^ self error: 'Integer is an abstract class. Make a concrete subclass.'].
^ super new

I looked for new higher up in the hierarchy(super), but could not see it. Maybe I am a bit dumb still with looking up.

I tried on SmallInteger a new, but got back
Error: SmallIntegers can only be created by performing arithmetic.

I then checked and noticed that SmallInteger actually have new and basicNew implemented (override)

So the error I got on smallinteger was from the override
LargeInteger has no override, but has a “silent" error

This seems a bit weird to me

Just so you know I also tried
Do-it myVar := LargeInteger new: 10000
Print-it myVar class. -> LargeInteger
Dot-it myVar := myVar + 1

The last statement hangs the image! (Tried 3 times)

Comment:
1. I am surprised that Do-it did not give me an error on the new: (there is a message is the hierarchy of new:neg and maybe the neg is optional?)
2. The new: seemed to have created 10000 LargeIntegers
3. I tried the new: also with just 5, and same result, image hang. (I thought 10,000 was maybe a very large loop for the + 1..)

Did I damage something in the image maybe? I started this one just yesterday to look at MOOC week1.

I do not need LargeIntegers for now but …

This is Pharo 6.0 64 Bit on Mac OSX Sierra 10.12.5 (iMac 27, 2.9GHz Intel Core i5, 16GB RAM)

Regards

Koos Brandt
0824542028