Latex3: Documenting F form when TF does not exist

What gives you the idea these are deprecated?

What gives you the idea these are deprecated?

The compilation of the following MCE:

\documentclass{article}
\begin{document}
\ExplSyntaxOn
\file_if_exist_input:nTF {Foo} {Bar} {Baz}
\ExplSyntaxOff
\end{document}

returns:

! LaTeX3 Error: Use \file_if_exist:nT and \file_input:n not
(LaTeX3) \file_if_exist_input:nTF deprecated on 2018-03-05.

Type to continue.
...

l.21 \file_if_exist_input:nTF
{Foo} {Bar} {Baz}

Ah, right: this one is tricky as we've kept the n and nF forms.

BTW, I don't understand why it has been deprecated as it would be still useful for cases as the following one:

\file_if_exist_input:nTF {foo}{
  \pdfbookmark[1]{Foo}{foo}
}{
  \msg_warning:nn{module}{`foo~file~is~missing!}
}

Okay, this can be achieved with:

\file_if_exist:nTF {foo}{
  \file_input:n {foo}
  \pdfbookmark[1]{Foo}{foo}
}{
  \msg_warning:nn{module}{`foo~file~is~missing!}
}

but that's less handy.

The problem is 'where does the T branch live' - it's not at all clear whether such a branch goes before or after the input, and whichever one picks, there will be use cases for the opposite one.

BTW, I don't understand why it has been deprecated as it would be still useful for cases as the following one:

Why would you execute the \pdfbookmark after the processing of the file?

Why would you execute the \pdfbookmark after the processing of the file?

Oooops! Before, of course :smile:

See #253, which suggests \file_if_exist_input:nnTF (file) (preliminary set up) (true code after the file is input) (false code if not input). I think we should continue that discussion there.

Here we should keep the indexing issue: the deprecated function \file_if_exist_input:nTF shouldn't be indexed. What is happening is that \file_if_exist_input:nF is indexed as its base form \file_if_exist_input:nTF. This is similar to #618 where l3doc assumes that some base form exists when it doesn't actually exist. Probably the fixes will be related.