[Uristqwerty]

I don't know about anyone else, but I like aligning certain things at half-indents (labels/cases half an indent back, so you can skim the silhouette of both the surrounding block and jump targets within it; braceless if/for bodies to emphasize their single-statement nature (that convention alone would have made "goto fail" blatantly obvious to human readers, though not helped the compiler); virtual blocks created by API structure (between glBegin() to glEnd() in the OpenGL 1.x days)).

Thing is, few if any IDEs support the concept, so if I want to have half-indents, I must use spaces. Unfortunately, these days that means giving up and using a more common indent style most of the time, as the extra bit of readability generally isn't worth losing automatic formatting or multi-line indent changes.

[takeda]

So you are the person that ruins it for everyone (are you emacs user by any chance?). Tabs are more versatile, you can even use proportional fonts with them. Projects end up using tabs because many people end up mixing them together (unknowingly or in your case knowingly using configuration that is unavailable in many IDEs).

BTW when you mix spaces with tabs you eliminate all benefits that tabs give (for example you no longer can dynamically change tab size without ruining formatting.

[Uristqwerty]

If I were an emacs user, I'd figure out how to write a plugin to display tab-indented code to my preferences.

No, I used to be a notepad user (on personal projects, not shared work) (you can kinda see it in the use of indentation to help convey information that IDEs would use font or colour to emphasize), and these days use tabs but longingly wish Eclipse, etc. had more options in their already-massive formatting configuration dialogues.

[takeda]

The reason I asked is that I believe this behavior is what Emacs does by default (actually don't know if by default, but saw this from code produced by Emacs users) e.g.

<tab>(inserts 4 spaces)<tab>(replaces 4 spaces into a tab that is 8 columns)<tab>(adds 4 spaces after the tab)<tab>(replaces with two tabs and so on)

Unless I misunderstood what formatting you were using.

[mntmoss]

You can use empty scope braces for this task in most languages. It's not a "half-indent" but it gives you the alignment and informs responsible variable usage.