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adding an element to an empty array

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abdelghani ALIDRA

adding an element to an empty array

Hi guys,

Is there any way to add an element to an empty array (must not use new: anElement)?

Cheers

Henrik Sperre Johansen

Re: adding an element to an empty array

On 29 Jun 2015, at 2:18 , abdelghani ALIDRA <[hidden email]> wrote:

Hi guys,

Is there any way to add an element to an empty array (must not use new: anElement)?

Cheers

It sounds like you want to use an OrderedCollection, not an Array.

Those will grow and shrink as needed when you use add:/remove: calls.

Cheers,

Henry

Peter Uhnak

Re: adding an element to an empty array

Or if you want to create an array with elements already in it (this works both for array and collections) you can also do

~~~~~~~~~~

{ anElement } "dynamic array syntax, Pharo-only"

~~~~~~~~~~

~~~~~~~~

#('element') "static array, works only for scalars"

~~~~~~~~

~~~~~~~~~~~~~~~~

Array with: anElement "constructor method, works also with more elements... Array class>>with:with:with:..."

~~~~~~~~~~~~~~~~

~~~~~~~~~~~~~~~~~~~~~~~~~

OrderedCollection with: anElement "as above, but creates a collection instead"

~~~~~~~~~~~~~~~~~~~~~~~~~

Peter

On Mon, Jun 29, 2015 at 2:23 PM, Henrik Johansen <[hidden email]> wrote:

On 29 Jun 2015, at 2:18 , abdelghani ALIDRA <[hidden email]> wrote:

Hi guys,

Is there any way to add an element to an empty array (must not use new: anElement)?

Cheers

It sounds like you want to use an OrderedCollection, not an Array.
Those will grow and shrink as needed when you use add:/remove: calls.

Cheers,
Henry

Sven Van Caekenberghe-2

Re: adding an element to an empty array

In reply to this post by Henrik Sperre Johansen

> On 29 Jun 2015, at 14:23, Henrik Johansen <[hidden email]> wrote:
>
>
>> On 29 Jun 2015, at 2:18 , abdelghani ALIDRA <[hidden email]> wrote:
>>
>> Hi guys,
>>
>> Is there any way to add an element to an empty array (must not use new: anElement)?
>>
>> Cheers
>
> It sounds like you want to use an OrderedCollection, not an Array.
> Those will grow and shrink as needed when you use add:/remove: calls.

That being true, there are actually #copyWith: and #copyWithFirst: that will do the trick, although inefficiently.

> Cheers,
> Henry