Opposite of "nesting" a structure

Generally, if some object is nested, it is in a hierarchy level below another object. For example:

* Layer 1
  - Layer2

"Layer 2 is nested in Layer 1". What do I call it, if I would "de-nest" Layer 2? Like:

* Layer 1
* Layer 2

I have ... Layer 2.

"De-nesting" sounds made up. "To place beside" would describe it, but I would prefer a similar short and snappy verb like "to nest".

This is often called flattening. Below is a reference from the Jargon File. Also if you type "flatten list", for example, into Google, you will see that it's a commonly used term.

flatten: vt.

[common] To remove structural information, esp. to filter something with an implicit tree structure into a simple sequence of leaves

[Jargon File]

Unnesting appears to be the antonym:

Nesting and unnesting:

• The transformation of a nested relation into 1NF is called unnesting.

Nest and Unnest Operators in Nested Relations:

• By distinguishing nested attributes as Decomposable and Non-Decomposable, it is proved that for all nested relations, unnesting and then renesting on the same attribute yields the original relation subject only to the elimination of duplicate data. Therefore, the statement that was popular in nested relations research: "Unnesting and then nesting on the same attribute of a nested relation does not always yield the original relation" is reconsidered.

Since the object in question is moving up the hierarchy one level, you could say that it has been promoted. Eg "Layer 2 was promoted to the top level".

http://www.dictionary.com/browse/promoted

to advance in rank, dignity, position, etc. (opposed to demote ).

Another option is hoist or hoisting. When you hoist an item in an outline, you are moving it from a deeper branch to be alongside a parent or grandparent branch. It often involves moving all of the children of the selected item as well, grafting the branch further up the tree.

This usage comes from its use in outlining tools such as OmniOutliner, TinderBox, TheOutlinerOfGiants.com or VoodooPad, plus even older tools such as ThinkTank or MORE.

I would simply say you unindented Layer 2:

Originated in the 1980s when computers made it trivial for anyone to move text around on a page.

To remove the indentation; to move a block of text closer to the left margin.

I had to unindent the first line of each paragraph so that my essay would fit onto one side of paper.