Lib.rs

Imagine this but with pretty colors:

$ latexdef def @newcommand author box parskip thanks begin bedgin
\def is primitive.
\@newcommand = #1[#2] -> \kernel@ifnextchar [{\@xargdef #1[#2]}{\@argdef #1[#2]}
\author = #1 -> \gdef \@author {#1}
\box is primitive.
\parskip is primitive.
\thanks = #1 -> \footnotemark \protected@xdef \@thanks {\@thanks \protect \footnotetext [\the \c@footnote ]{#1}}
\begin = #1 -> \@ifundefined {#1}{\def \reserved@a {\@latex@error {Environment #1 undefined}\@eha }}{\def \reserved@a {\def \@currenvir {#1}\edef \@currenvline {\on@line }\csname #1\endcsname }}\@ignorefalse \begingroup \@endpefalse \reserved@a

Further:

$ latexdef --help
latexdef 0.1.0
Rebecca Turner <rbt@sent.as>
Prints definitions of LaTeX macros.

USAGE:
    latexdef [FLAGS] [OPTIONS] <COMMAND>... --documentclass <CLASS> --engine <ENGINE>

FLAGS:
    -e, --expl3      Enable LaTeX3e features with the expl3 package
        --math       Load common math packages (amsmath, amssymb, amsthm, mathtools)
    -h, --help       Prints help information
    -V, --version    Prints version information

OPTIONS:
        --documentclass <CLASS>    Document class to use [default: article]
        --engine <ENGINE>          TeX engine to run. [default: latex]
    -p, --packages <PACKAGE>...    Packages to load

ARGS:
    <COMMAND>...    Commands to show definitions of

Install with:

cargo install latexdef