In-place attribute removal

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1

https://learninghub.kx.com/forums/topic/in-place-attribute-removal

Is there any way to do this? # looks to always be creating a copy of the original list for g/u, whether it's applied on a list reference or value. I wrote a C function to set the list object's u member (x->u) to 0, and from within q called this function and followed it up with re-applying the attribute (g#) and this combination seems to clear the attribute without making a copy and also removes the references to the previous attribute data, allowing it to be garbage collected by .Q.gc. Is there another way? Thanks in advance.

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According to the docs at Set Attribute | Reference | kdb+ and q documentation - Kdb+ and q documentation (kx.com) :

Setting or unsetting an attribute other than sorted causes a copy of the object to be made.

 

Using a C function as a workaround might work but it might also break in a future version when kdb+ internals change.