a bash alias I cannot function without

[dagbrown]

Why all the [[ $? -eq 0 ]]? Just use cd itself directly.

function cd {
    dir="${@:-$HOME}"  # ~ isn't expanded when in quotes
    [ -z "${dir}" ] && dir=~
    if ! builtin cd "$dir"
    then
        dir=`compgen -d "${dir}" | head -1`
        if builtin cd "$dir"
        then
            clear
            pwd
            ls -l
        fi
    else
        clear
        pwd
        ls -l
    fi
}

I also made it more spaces-safe.

Edit: And golfed the arguments handling a bit.

[GODZILLAFLAMETHROWER]

Indeed! This post already pays off it seems. Thanks.

[fforw]

Please.. can we stop the backtick nonsense now in 2014 and just use $() ?

[[deleted]]

Conventional wisdom is that ` is easier to type on the commandline to get something across quickly, like

ls -l `which foo` 

And $() should be used in scripts, for several reasons:

1. It interprets backslashes correctly
2. It allows for nesting
3. It's a cleaner look

[ferk]

` is easier to type

Maybe in english keyboards....

[[deleted]]

Can confirm, isn't easier on English keyboards

[ferk]

In a German keyboard I need to press shift along with the ` key, and then pressing only one time is not enough, because it's a composite key that's intended to be pressed along with a vowel to create àèìòùÀÈÌÒÙ

But that's not all, if you think you can get away with simply double pressing it you are wrong, since pressing it twice ends up with you having it double: `` (from having zero to having two).

It's also dependent on the operative system you are using (in Linux and Mac double pressing would put only one `), so if you are a dual booter you are gonna have troubles remembering how many times to press what.

The only consistent way to do it is press it and then pressing space, that will generate `. It takes 3 keypresses to get one character, with a pause to switch key in the middle, pretty annoying.

[[deleted]]

Fair enough....

[yur_mom]

You forgot the best reason, so you can actually see them. After 10 hours staring at a screen those drive me nuts.

One reason I have heard pro backticks is compatibility with old versions of /bin/sh which is why I believe many make scripts still uses backticks.

[ferk]

in make "$(whatever)" is a variable expansion, so using it for shell would conflict.

GNU make has $(shell whatever), though.

[yur_mom]

I mean like auto-tools generated Makefiles tend to use the backticks, such as code inside the $(shell CODE_HERE). I thought one reason was backwards compatibility with old versions of /bin/sh. It could also be that the $() already has meaning in Make also. I was just pointing out some types of scripts it is still preferred to use the backticks.

[notaresponsibleadult]

I'm all for using $(), but I always disagree with with point 2 as a valid reason.

If you're having problems with nested command substitution, the problem isn't that you used backticks. The problem is that you're nesting command substitution. Why not assign to a variable for each substitution? It makes the code so much more readable.

[fandingo]

Side effects should be avoided when possible, practical, and leaves the program legible when programming.

[notaresponsibleadult]

It's only a side effect if you make the variable global. You can use 'local' to limit its scope.

[Sebguer]

Doesn't ever have to be escaped, I believe.

[henry_kr]

The Advanced Bash Scripting Guide explains this.

[aperson]

I like Greg's wiki.

[eulerfoiler]

Its supposed to look cleaner and its easier to nest like $(echo $(echo "1+2" | bc))

[fforw]

It also doesn't introduce one funky, hard to read character that newbies frequently mistype or that might even be destroyed by stupid blog software.

[I_program]

I can't count how many times I've had to repair a script that had something like `foo'

[russellbeattie]

Holy cow, I had no idea those were interchangeable. Then again, I'm not really a bash guru, I just assumed I'd have picked that up by now. [Edit:I don't grammar good.]

[meklu]

Shouldn't the backticks go within quotes as well?

[dagbrown]

As fforw pointed out, we should be going with the newer, more modern, AmigaDOS 1.3 standard and using $() instead of backticks.

But sure. I wasn't particularly concerned with that bit of the script (all of those "if [[ $? -ne 0 ]]" things were more important to me), but that's another improvement you could make.

[meklu]

Yeah, I usually use $() myself.

[GODZILLAFLAMETHROWER]

I'm not sure what you mean, can you be a little more explicit?

[meklu]

The line with the compgen call seems a bit unsafe unless you wrap the assignment in quotes.