This is a good example demonstrating a generic use case for a simple package using l3build.
This package is set up to produce two PDF files: one including the user documentation for the package, and the second, with ‘-code’ suffix, which includes both the user documentation and the typeset package code.
Note that these are produced by the two .tex files, which simply set typesetting options and read in the .dtx docstrip file so only one source file needs to be maintained.
A variety of alternative docstrip arrangements can be set up to similar effect; the arrangement here is chosen for simplicity.
As the .dtx package file grows larger, it may be sensible to split it up into multiple files, including separating the user documentation from the code itself.
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