\IfFileLoadedTF missing

[Rimole]

Brief outline of the enhancement

Minimal example showing the current behaviour

pdflatexing

\RequirePackage{latexbug}       % <--should be always the first line (see CONTRIBUTING)!
\documentclass{article}
\begin{document}

\IfFileLoadedTF{l3backend-pdftex.def}{\message{l3backend-pdftex.def has been loaded.}%
}{\message{l3backend-pdftex.def has NOT been loaded.}%
}
  
\end{document}

gives ! Undefined control sequence. \IfFileLoadedTF{l3backend-pdftex.def}{\message{l3backend-pdftex.def has...,
while \IfPackageLoadedTF and \IfClassLoadedTF are defined.

Minimal example showing the desired new behaviour

Define \IfFileLoadedTF.

[muzimuzhi]

Nice complement to

• \IfFileAtLeastTF missing #1015

[josephwright]

Is there a concrete use case here?

[Rimole]

There is a somewhat related case at https://tex.stackexchange.com/q/98108 and I use it to check whether some files (.def, .cfg etc.) are still being loaded or some update removed the requirement. (Look in the log file? "Manually"? I'm too lazy for that.)

[FrankMittelbach]

problem is that most files aren't detected by this approach, you have to have a file that contains a \ProvidesFile line, that is true for some .def files but not for all nor for many .cfg files etc. Which is why I don't really think this is very useful.

[FrankMittelbach]

added the commands

[Rimole]

@FrankMittelbach

1. Thank you!
2. In ltnews39.tex, line 359, \cs{IfClassLoadedWithOptionsFF} should be ...TF instead ...FF - right?

[FrankMittelbach]

it should, sigh :-) thanks