Comment by Y_Y

Comment by Y_Y 19 hours ago

16 replies

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On that point, I see an awful lot of code that uses dotslash as if it was necessary for files in the current directory.

You only need to prepend dotslash to a filename in order of disambiguate invocations of executables in the the current directory (and not a subdirectory).

This is because bare commands will be looked up in $PATH, rather than among executable files in $PWD.

It strikes me as weird copycat (without understanding) programming to just have it wherever you're referring to a local file. In fact I prefer to invoke `bash foo.sh` rather than `mv foo.sh foo; chmod +x foo.sh; ./foo.sh`. (This assumes that I don't need to rely on something special in the shebang line.) This also lets you use tab-completion as normal, as well as adding flags for bash like -x.

(I know you could use it for clarity when an argument could look like a string or a file, but I don't think that's usuaully the purpose.)

PhilippGille 19 hours ago

One issue is when the path is not interpreted by the shell but by a program which plays by different rules.

For example in Go:

  $ cd /path/to/go/repo
  $ go run cmd/myapp
  package cmd/myapp is not in std (/usr/local/go/src/cmd/myapp)
  
  $ go run ./cmd/myapp
  Hello, World!
And then people don't want to think about when your path is for the shell and when it's a CLI param and how the CLI treats it, and just use the version that always works.
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  • Y_Y 18 hours ago

    Thanks, this is the first good reason I've seen! Seems crazy to me that the go tool does that, but maybe I just lack sufficient unix-nature.

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    • zahlman 17 hours ago

      This allows it to disambiguate between system path syntax and the language's syntax for symbolic names.

      Similarly, package installers can use this to disambiguate between "install the local file with this exact name" and "look up a file on the index for the named package".

      Reply View 0 replies
  • catlifeonmars 13 hours ago

    That’s because cmd/myapp is not a local path, it’s a universal path. It makes more sense when you type go run github.com/user/name/cmd/myapp

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  • umanwizard 14 hours ago

    This is one of the papercuts of go that I find way more annoying than is rational.

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Bleibeidl 19 hours ago

I'm pretty sure most people use it to make clear it's a relative path. It takes mental load off the one reading the code. That's why I pretty much always use it, not only when executing things.

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aidos 19 hours ago

./<tab> completes nicely. Ambiguity is removed. There’s no chance of accidentally running the wrong executable.

So I think you and I differ on this one, but none of this is a hill I care to die on.

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lynx97 19 hours ago

For executables, it is actually necessary to prepend ./ iff . is not in $PATH. And . is usually not in $PATH for security reasons.

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mjw1007 19 hours ago

It makes tab completion work.

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  • jagged-chisel 19 hours ago

    At the start of a line? So you want to run a script or executable in the current directory. PATH doesn’t contain . and ./ is necessary.

    As an argument in a line? My shell offers completion from the current directory without ./ just fine.

    Reply View 1 reply
    • alganet 7 hours ago

      Let's say you have 100 programs in your PATH that start with the letter "g", but only one program in the current folder that starts with "g". You type `./g[TAB]` so it autocompletes automatically to the local program instead of cycling through dozens of results you know you don't want.

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amonith 19 hours ago

I use it for autocomplete... e.g ./f<tab> and enter. If I don't do it the terminal literally hangs for a split second and gives me a lot useless suggestions. I rarely type full words.

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teddyh 19 hours ago

Similarly, many people needlessly append a slash to every directory name.

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  • SoftTalker 12 hours ago

    Makes it clear you're naming a directory and not a file.

    I also alias 'ls' to 'ls -F' so that directories have a / appended, makes it easier to understand the output.

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  • chuckadams 12 hours ago

    It's handy when the directory might not exist, happens all the time in git checkouts. Raise your hand if you've ever moved something to tmp and created a file called tmp.

    Usually it's tab-complete adding the slash though, I don't go typing it in.

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