pub fn preceding_para_sibling(node: &Node) -> boolExpand description
Does an ltx:para element immediately precede node? Both prune_empty_para
(to decide ltx_pruned_first) and the first-paragraph ltx_noindent stamp
(tex_paragraph.rs, OXIDIZED_DESIGN #143) ask this: a paragraph with no
preceding ltx:para sibling is the first paragraph of its parent, structurally
— a signal robust to how many stray \pars fired before it (which varies by
TeX Live year / dump vs no-dump).