Special punctuation marks

Is there an easy way to render special punctuation marks present in some fonts, such as double question mark, double exclamation mark, or interrobang?

Also, is there a font (preferably open-source) featuring question comma and exclamation comma characters?

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The answer depends on the engine you're using. –  egreg Jun 27 '12 at 8:32

I sometimes like to use the Hoefler Text ampersand in the headings of my CV, even though my font of choice for the remainder of the CV is not Hoefler; I do this by adding the following to the preamble:

``````\usepackage{xltxtra} % Requires use of XeTeX or XeLaTeX
\newcommand{\amper}{{\fontspec[Scale=.95]{Hoefler Text}\selectfont\itshape\&}}
``````

and using `\amper` whenever I want that special ampersand in a header (but `\&` when I want the 'normal' ampersand elsewhere).

Note that `xltxtra` requires that you use XeTeX or XeLaTeX. If--as I understand--you've found a font that represents the interrobang, double exclamation, or double question mark characters in a way you particularly like, but is not the font you're using in the rest of the document, then a solution like this could work for you, I think . . .

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I guess it should be sufficient to load just `fontspec` and not the whole `xltxtra`. –  canaaerus Jun 27 '12 at 7:27
It's more efficient to declare `\newfontfamily{\hoefler}[Scale=.95]{Hoefler Text}` in the preamble and then `\newcommand{\amper}{{\hoefler\itshape\&}}`, so XeLaTeX doesn't have to do all computations at every call of `\amper`. –  egreg Jun 27 '12 at 7:52