hfy-begin-span-handler

hfy-begin-span-handler is a variable defined in `htmlfontify.el'.
Its value is

hfy-begin-span

Documentation:
Handler to begin a span of text.
The signature of the handler is (lambda (STYLE TEXT-BLOCK
TEXT-ID TEXT-BEGINS-BLOCK-P) ...). The handler must insert
appropriate tags to begin a span of text.

STYLE is the name of the style that begins at point. It is
derived from the face attributes as part of `hfy-face-to-css'
callback. The other arguments TEXT-BLOCK, TEXT-ID,
TEXT-BEGINS-BLOCK-P are non-nil only if the buffer contains
invisible text.

TEXT-BLOCK is a string that identifies a single chunk of visible
or invisible text of which the current position is a part. For
visible portions, it's value is "nil". For invisible portions,
it's value is computed as part of `hfy-invisible-name'.

TEXT-ID marks a unique position within a block. It is set to
value of `point' at the current buffer position.

TEXT-BEGINS-BLOCK-P is a boolean and is non-nil if the current
span also begins a invisible portion of text.

An implementation can use TEXT-BLOCK, TEXT-ID,
TEXT-BEGINS-BLOCK-P to implement fold/unfold-on-mouse-click like
behavior.

The default handler is `hfy-begin-span'.