0.2
The short answer is: to make things easier with filemanagers.
Let's see how things would be without the AND operator, by taking the valid tagsistant query ~/tags/t1/AND/t2/AND/t3 and rewriting it, step by step. Keep in mind that you are using a filemanager. Here we go:
- you enter ~/tags directory
- tagsistat lists all the tags available
- you enter t1
- the path is now ~/tags/t1, so tagsistant must list all the files tagged as t1 but also the whole list of available tags to permit further navigation
- you enter t2
- the path is now ~/tags/t1/t2/. Once again, tagsistant must list all the file tagged as both t1 and t2, together with the whole list of available tags to permit further navigation
- ...
As you can see, the result listed ad 4. and 6. are a huge set of entries. Introducing the AND operator mitigate the problem since the steps become:
- you enter ~/tags directory
- tagsistat lists all the tags available
- you enter t1
- the path is now ~/tags/t1, so tagsistant must list all the files tagged as t1 and the AND operator alone
- you enter the AND operator to keep building the query
- now tagsistant list the whole set of available tags, but not the files
- you enter t2
- tagsistant list all the files tagged as t1 and t2 with the AND operator alone
- ...
If you still don't understand how adding an operator can simplify your life, just think how could be scrolling a list formed by 3000 tags and 10000 files at points 4. and 6. of the first list. Better split it in two lists, isn't it?