LaTeX package 'ifetex'
Copyright (c) 2011-2018 by Martin Scharrer <>
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This small package provides the if-switch \ifetex which indicated whether
e-TeX is available or not.

The package can be loaded as LaTeX package using `\usepackage{ifetex}` or in
plainTeX using `\input ifetex`. In both cases it aborts silently if the \ifetex macro
is already defined.

The package currently test if \eTeXversion is defined as a primitive and
assumes e-TeX if so.