\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{ifmtarg}[2026/10/09 v1.2c check for an empty argument]
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\catcode`\Q=3
\long\gdef\@ifmtarg#1{\@xifmtarg#1QQ\@secondoftwo\@firstoftwo\@nil}
\long\gdef\@xifmtarg#1#2Q#3#4#5\@nil{#4}
\long\gdef\@ifnotmtarg#1{\@xifmtarg#1QQ\@firstofone\@gobble\@nil}
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\endinput