Spec for level attribute

[matatk]

Here is how the level will be worked out. We encourage people to use the first "it works out the level automagically" approach.

• When level is not present, the nesting level is calculated from the document structure (as originally), and aria-level and level are set to that level.
  • If level is present, but is not a non-zero positive integer, a console message is logged and the unusable value is ignored (so the document structure is used, as above).
• When level is present and is a non-zero positive integer, it is preserved and aria-level is given the same value. The document structure is not used.