[OS X TeX] dropped parentheses

[Nitecki, Zbigniew H.]

What I thought was a simple macro definition is yielding puzzling results.
The full testfiles are attached below.  Bottom line:
with these definitions

\newcommand{\dist}[2]{\ensuremath{\operatorname{dist}(#1,#2)}}% distance function
\newcommand{\distsub}[1]{\ensuremath{\operatorname{dist}_{#1}}}%subscripted distance name
\newcommand{\dists}[3]{\ensuremath{\distsub{#1}(#2,#3)}}%subscripted distance function


\newcommand{\distX}[1]{\ensuremath{\distsub{X}}}
\newcommand{\distY}[1]{\ensuremath{\distsub{Y}}}


why are my closing parentheses (not part of the macro) dropped?


Zbigniew Nitecki
Department of Mathematics
Tufts University
Medford, MA 02155

telephones:
Office    (617)627-3843
Dept.    (617)627-3234
Dept. fax    (617)627-3966
http://www.tufts.edu/~znitecki/



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