Proposal: Mark cat file.txt | or < file.txt as preferred in the style guide

[Managor]

cat file.txt | and < file.txt do the same exact thing. For this reason it would be beneficial to prefer using one over the other in the pages. The advantage of < file.txt would be that we don't need to involve any other commands but it's less known than piping. Thus new users might not understand what it does. If we started using it commonly, the knowledge of what it does might spread. cat file.txt | has the advantage that everyone has seen it being used.

This should not be a hardline stance. Each command should be judged case by case based on how it's most commonly written on the internet, but when in doubt this guideline could be used.

[jxu]

The "useless use of cat" IMO is only to show you can pipe stuff in while < file.txt looks a little awkward not flowing left-to-right. Many (but not all) programs, e.g. jq can read input from file natively, but maybe it is more useful in a pipeline, e.g. from the output of curl.

[Managor]

The command flowing from left to right is a very strong argument. < file.txt is not technically part of the command and thus disrupts it.