Danbooru

pile_of_books -> book_stack

Posted under Tags

An implication the other way around would probably make more sense, as not every pile is a stack.

But not every stack is a pile, either. If the book stack is fairly neat/orderly and straight in a bookshelf or on a desk (rather than stacked haphazardly), it's not really a pile.

It should be left as it is. Some book stacks should be tagged as piles, but not all. And not every book pile (heap) is stacked.

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