How to rename a command for a symbol
Don't use \mathrm
for defining operators: the spacing might be wrong. Compare
\[ \mathrm{int} A \]
versus
\[ \mathop{\mathrm{int}} A \]
There's no need to use the complicated second construction, because amsmath
provides an easy way to get it.
\usepackage{amsmath}
\let\intgrl\int % keep the original definition of `\int`
\let\int\relax % to avoid a "spurious" error message
\DeclareMathOperator{\int}{int}
\DeclareMathOperator{\Int}{Int}
However, I wouldn't redefine \int
and use
\DeclareMathOperator{\sint}{int}
\DeclareMathOperator{\sInt}{Int}
("s" for "set").
you probably need to use something like:
\let\intgrl\int
\def\int{\mathrm{int}}
\def\Int{\mathrm{Int}}
In one of the source files for The Comprehensive LaTeX Symbol List by Scott Pakin there is this
% There are a number of symbols (e.g., \Square) that are defined by %
% multiple packages. In order to typeset all the variants in this %
% document, we have to give glyph a unique name. To do that, we define %
% \savesymbol{XXX}, which renames a symbol from \XXX to \origXXX, and %
% \restoresymbols{yyy}{XXX}, which renames \origXXX back to \XXX and %
% defines a new command, \yyyXXX, which corresponds to the most recently %
% loaded version of \XXX. %
Somewhere else he mentions that the commands are avialable in the savesym
package (though that didn't seem to have any docmentation, hence the above copy past). I could get the package through miktex package manager.
Check out the file symbols.tex for more info (he re-implements the commands).