In my answer to another question, I've used an upside-down A as a V-with-strikethrough character. After playing with it a bit, I've realized that this doesn't give appropriate kerning if the character is followed by a subscript, presumably because the A is placed in a rotatebox.
It seems that the best way to get around this is to place the upside-down A in a zero-width box using llap/rlap and then insert an invisible V, so that the same kerning as would be used for a regular V is applied. Unfortunately, if I use \phantom{V}
, it seems that result is a box (no kerning).
Is there a \phantom
-like function which makes the character invisible/non-selectable but maintains the same kerning?
Edit: I came up with a hack which checks to see whether the following text is subscript, then applies kerning if it is. The key component is
\@ifnextchar_{\kern-0.17em}{}
% if the next char is "_", add negative kerning
% otherwise, do nothing
And the full \Vol
command is then
\makeatletter
\newcommand{\Vol}{\rotatebox[origin=c]{180}{\ensuremath{A}}\@ifnextchar_{\kern-0.17em}{}}
\makeatother
Nonetheless, if there is a more elegant way of keeping the exact kerning from the original V, I'd be interested to hear about it.
\forall
, which is already an upside-down A? – Arun Debray Dec 5 '15 at 8:10\exists
didn't work so well, but I didn't address its kerning. – Arun Debray Dec 5 '15 at 8:26\phantom
can never be the nucleus of a math atom (it yields a different type of node, a “four-way choice”), so it cannot carry a subscript. – GuM Sep 29 '17 at 9:57