Piping (Command line options)

[syxolk]

Currently we have this:

• indentex [DIRECTORY]
• indentex [FILE]

What I want to add:

• indentex [FILE] --stdout (write to stdout)
• indentex -o [OUTFILE] (read from stdin)
• indentex --stdout (read from stdin and write to stdout)
• indentex [FILE] -o [OUTFILE] (no piping at all; just here for consistency)

It's a bit weird to have the --stdout in the first place but I don't see any other way to stay compatible.

[mp4096]

Hm, a couple of points:

1. This will require quite a lot of changes in the code, e.g. breaking down some functions and introducing new ones. You've been already working on it in the piping branch.
2. I'd prefer explicit over implicit. Why not have an --stdin flag?
3. I'd prefer -t/--to and -f/--from flags as in pandoc instead of -o. The latter does not have a 'from' or 'input' counterpart, does it?

Apart from this: I find the multi-nesting if-else if-else branches really clumsy and un-elegant. Do you know a fancy pattern for this? The only thing I can think of is matching on tuples:

match (flag_a, flag_b, flag c) {
    (true, false, false) => foo(),
    (false, true, false) => bar(),
    _ => (), // invalid combination
}

[mp4096]

Thinking about it: Why not --to-stdout and --from-stdin flags? I'd rather type 10 chars more than have inconsistent and ad-hoc flags/commands (like git, unfortunately).

[syxolk]

1. Most changes are now in main.rs.
2. I tried to mimic the behavior of gcc. However, it's probably better to require a special flag to use standard input instead of making assumptions if no input file is given.
3. Adding --from would not be easily backwards-compatible.

[mp4096]

Ok, I'll take a look at it today!