# Which constructs in TeX/LaTeX and their packages have classification \mathinner?

Which constructs in (La)TeX and (La)TeX packages have classification \mathinner?

The TeXbook mentions:

• fractions
• \left...\right constructions
• \ldots, \cdots, \ddots

Which fractions - all? Do other frequently used packages (e.g. AMS-LaTeX) define other constructs (e.g. I'm assuming all types of triple dots in AMS-LaTeX)?

One might expect the following to generate \mathinner, but they don't:

• \bigl...\bigr (and the larger-size analogues)
• \lvert...\rvert
-
There's no reason why \bigl...\bigr should be inner, nor \lvert...\rvert. – egreg Jan 29 '14 at 7:45
@egreg 1. You can think of them as an instantiation of \left...\right, which in effect reduces to one of the \σl...\σr-sizes. 2. A user might not know that \σl and \σr don't need to be paired. – Lover of Structure Jan 29 '14 at 7:58

amsmath defines \@cdots as \mathinner; this in turn is used for \cdots, \dotsi, \dotsb, \dotsmand \intdots.
\mathellipsis and \ddots are so defined in fontmath.ltx.
mathtools doesn't add anything obvious.