Marco Cimarosti scripsit:

> Not necessarily: each glyph in the "visual store" could contain (a)
> pointer(s) to the character(s) in the "back store" to which it maps.

That just boils down to memoizing the function. You could do the same
in a visual-order input system, where the back store points to the
visual store instead.

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Once put the rest of us dowan. [on xml-dev]
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