how do i check for name clashes

[whysthatso]

how do i avoid or check if any of my existing aliases clash with binary names in $PATH?

i.e. i would like to alias long commands with single letters or short alternative names. if i will install a package that provides a binary with an exact name match, how would i discover that? trial and error, or is there some sort of mechanism? or should i namespace all my fishshell functions?

[faho]

If you want to know if a command (i.e. an executable file somewhere in $PATH) by a name exists, use command -q to just tell you yes/no via the return status, or command -s to give you the path, e.g.

> command -q foobar
> echo $status
# either 0 if it exists or 127 if it doesn't

> command -s foobar
/usr/bin/foobar

To check for all of your functions:

command -s (functions)

For the most part, this isn't really a problem. If you have a function of a name and a command, using just the name will run the function, but you can use command name to run the command. E.g.:

function foobar
   echo Hello I am the function
end

foobar # prints "Hello I am the function

command foobar # runs /usr/bin/foobar

For instance, that command -s (functions) above will have printed a bunch of commands including ls, for which fish ships a wrapper that enables color. That wrapper uses command ls to avoid calling itself.

if i will install a package that provides a binary with an exact name match, how would i discover that?

Because functions take precedence, you can keep on using your existing function. If you then find out you need to use the command, you can use command thing if you need it sometimes, or you can then rename your function.

Just try not to trample on anything too well-known (apt is a terrible function name) and it's fine.

[whysthatso]

thank you for you comment.
so as i understand it, the actual option is running command foobar and see if that returns a non-zero status code.

just for the sake of argument:
imagine i have an existing function utility_foobar_prog and because the stars aligned in a weir way, the newest foobar package i just installed has utility_foobar app (of which i am aware as i am using it to run the packages main program), but it also has a sort of utility binary utility_foobar_prog (of which i am not immediately aware)

so i would have to sort of run a hook after an arbitrary package installation which would loop through all my fish functions, run them as command function and see if it spits out a zero return code.

would that be about right?

[faho]

so as i understand it, the actual option is running command foobar and see if that returns a non-zero status code.

No. command foobar will run the "foobar" command.

You want command -s foobar if you're interested in the path, or command -q foobar if you just want to know that there is a path.

so i would have to sort of run a hook after an arbitrary package installation which would loop through all my fish functions, run them as command function and see if it spits out a zero return code.

You could, yeah:

for f in (functions)
    command -q $f; and echo $f
end

This will find things that are both available as a function and a command. This will include aliases like function ls; command ls --color=auto $argv; end, where that dual nature is the point.

Again: This is basically a non-issue. Functions shadowing unrelated commands rarely happens in practice, and even if it does, you can use command foo to run the command instead of the function if you ever actually need to.

[whysthatso]

so as i understand it, the actual option is running command foobar and see if that returns a non-zero status code.

No. command foobar will run the "foobar" command.

You want command -s foobar if you're interested in the path, or command -q foobar if you just want to know that there is a path.

ah yes, that's what i meant to describe, thank you.

so i would have to sort of run a hook after an arbitrary package installation which would loop through all my fish functions, run them as command function and see if it spits out a zero return code.

You could, yeah:

for f in (functions)
    command -q $f; and echo $f
end

This will find things that are both available as a function and a command. This will include aliases like function ls; command ls --color=auto $argv; end, where that dual nature is the point.

Again: This is basically a non-issue. Functions shadowing unrelated commands rarely happens in practice, and even if it does, you can use command foo to run the command instead of the function if you ever actually need to.

it gets a bit tricky when the name space is limited, cause that is how i stumbled upon the issue. in case of i.e. git status shortcut gs i suddenly shadowed the system's ghostscript binary, and only got an error when that gs then was called in a different context but didn't run the ghostscript binary. it was just a brief confusion, as the resulting error was rather explicit. but it just made me wonder if it is maybe still reasonable to consider some kind of background check. as i understand there is currently no such automatic process in fish, so i will consider that locally.

thanks again for the explanations. and for all the work going into this program :)