Blend mode "Clear" -> Why doesn't exist for layer ?

If a layer has a blend mode, it affects the entire layer, not just a part of it.

If the whole layer is "clear", it's fully invisible, mask or no mask. Anything below it is fully visible.

Or (more simply). If I try to sum up my request:
- To be able to modify a ‘Layer Mask’ (itself)(hide parts of this) with another Layer mask.

That is to say, a Layer mask, modified (itself) with another Layer mask (i.e. in a non-destructive way)!

I use Photoshop like a painter (for illustration). I need a dynamic and flexible solution.

No I don't think the result is erase all.

Exemple: If I draw a shape (in a part of my top layer with blend mode "Clear" (that I wish)). Then, this Shape It would be
the only part to be erased (masked if grey)the bottom layer !

I still don't understand how having a layer mask to a "dead" layer is non-destructive any more than any other layer mask?

If I need to work on a mask extensively, without affecting the image in any way until I'm ready for it, I just put it on a Levels layer without any adjustments. Then when I'm done, I move it to the intended layer. That's just one way; there are others.

What I do agree on, is that it would be nice to use, say, smart filters or adjustment layers on a mask. That's been suggested a few times, and is a feature request I support. In short, "smart masks". But that's a whole other story than blend modes.

Well, I'd like to have a ‘Layer Mask’ that I can modify in a NON-destructive way!

OK, I can hide a part of a lyer with a "layer mask".

BUT, if the shape is very complex (in the "layer mask"), and I want to modify the contents of the "Layer mask" -> Well, the "Layer mask" is modified in a DESTRUCTIVE way (they are pixels).

I'm looking for a way for hide a part of a layer, with a "Layer mask" which could be modified (itself) in a non-destrcucitve way).

The ‘Clear’ blend mode seemed to me to be a way of getting round the problem... But it doesn't exist in the layers...

How do I modify a ‘layer Mask’ in a NON-DESTRUCTIVE way?

I would have loved to have been able to put a "Folder" (with all contents) as ‘Layer Mask’ file. But none of this is possible.

A ‘Layer Mask’ can ‘simply’ be a pixel layer of grey values... This seems to me to be VERY VERY limited...

I'm an illustrator and I'm looking for creative ways to express myself!

Please, HELP me 😉

Well, basically it would be the equivalent of deleting the whole layer.

As for creating layer masks, there are so many ways to move layer masks around, swap them, group layers, smart objects etc - I really think you need to present a very compelling case why this would be needed.