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Show HN: Bish – Shell scripting with a modern feel

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Re: Show HN: Bish – Shell scripting with a modern feel

#24

Post by SwellJoe »

Perl started with roughly the same goal. awk, sed, grep, etc. weren't quite powerful enough, C was too low-level, Perl mixed them all up with real programming language features, while still being very usable in one-liners.

I don't think this improves on Perl. Being compiled to Bash might be interesting, if your deployment systems don't have Perl. It used to be unthinkable that any UNIX/Linux system wouldn't have Perl...but, several distros no longer install Perl by default (which is annoying as hell, to me, as Python isn't at all an acceptable substitute for one-liners and shell+ tasks). But, in that case, it would need to compile down to POSIX shell, because Ubuntu doesn't install bash by default, it uses ash (a small POSIX shell). So, bash has the exact same flaw as Perl for that use case.

Anyway, I don't generally think this adds things that I wish for when working with shell scripting, and having to compile it (even a quick compilation like this is likely to be) takes away one of the biggest benefits of scripting languages.

Re: Show HN: Bish – Shell scripting with a modern feel

#25

Post by username223 »

SwellJoe wrote: post #24

Perl started with roughly the same goal. awk, sed, grep, etc. weren't quite powerful enough, C was too low-level, Perl mixed them all up with real programming language features, while still being very usable in one-liners. I don't think this improves on Perl. Being compiled to Bash might be interesting, if your deployment systems don't have Perl. It used to be unthinkable that any UNIX/Linux system wouldn't have Perl…

This reminds me of another Larry Wall quote about the bad (old?) days: "It's easier to port a shell than a shell script." I'm honestly surprised and a bit disappointed that Bash isn't universal these days.

This seems like a really bad idea, since it apparently throws out good things like pipes, input/output redirection, wildcard expansion, and interactivity, but doesn't offer anything over the standard scripting languages.

Re: Show HN: Bish – Shell scripting with a modern feel

#26

Post by bracewel »

bishc wrote: post #5
basdp wrote: post #4

def printall(files) { for (f in files) { print(f); } } # cwd, ls, and cd are all builtin functions. dir = cwd(); files = ls(); print("Files in current directory $dir:"); printall(files); cd("/"); files = ls(); print("Files in root directory:"); printall(files); Whats wrong with this, much shorter Bash sequence: echo Files in current directory `pwd`: ls cd / echo Files in root directory: ls

(OP here). You're right: for simple tasks like listing files or changing directories, you probably don't need bish. I should come up with some better examples where bish wins in readability.

Seems like this could be really useful for writing larger packagers, installers or `curl | sh` type scripts...

Re: Show HN: Bish – Shell scripting with a modern feel

#27

Post by alphapapa »

shanusmagnus wrote: post #18
yramagicman wrote: post #7

Earlier quoted context omitted.

I believe the problem comes when trying to do stuff like check to see if a file is in a directory. I'm a ZSH user myself, and my default scripting language is Python for similar reasons to the OP's for inventing Bish. I can't for the life of me figure out the syntax for an if statement, especially for things like checking if files exist. Yes, Bash or Zsh have a shorter syntax for the example, but to do something like…

I'm with you. I have written a mountain of Bash scripts to solve various one-off problems, and I'm fucked if I can ever remember the nuances from one time to the next -- when to use [], when [[]], when () or (()), when the dollar sign precedes (), etc. Every single time I have to do anything in Bash I have to re-learn Bash. I suppose I keep using it because, even with having to re-learn every single element of Bash c…

Always use double-brackets [[ ]] if you're writing Bash (not sh) scripts. They are better.

Double-parentheses (( )) are only for arithmetic, e.g. "((count++))" or "echo $((1+1))"

The dollar sign precedes parentheses--i.e. $()--when you're substituting the output of a command, e.g. "echo Today is $(date)". It's easy to remember, because it's just like using the dollar sign for substituting the value of a variable, i.e. "date=$(date); echo $date".

You might want to look into the fish shell. Its scripting is much less idiosyncratic. You don't have to quote any variables, arrays, or command substitutions. e.g.:

    set foods apple banana 'cucumber casserole'
    for f in $foods
        echo $f
    end
prints:

    apple
    banana
    cucumber casserole
...not:

    apple
    banana
    cucumber
    casserole
...as would be the case if you forgot to quote "$foods" and "$f" in Bash.

Re: Show HN: Bish – Shell scripting with a modern feel

#28

Post by alphapapa »

I think that this may be unnecessary given the existence of the sh[1] Python module. It's incredibly simple and concise, e.g.:

    from sh import date, ls, egrep, git

    print date(), ls('~/project')
    print egrep(ls('~/project'), '-o', '\.py$')
    print git.add(egrep(ls('~/project'), '-o', '\.py$'))
[1] http://amoffat.github.io/sh/

Re: Show HN: Bish – Shell scripting with a modern feel

#29

Post by yramagicman »

shanusmagnus wrote: post #18
yramagicman wrote: post #7

Earlier quoted context omitted.

I believe the problem comes when trying to do stuff like check to see if a file is in a directory. I'm a ZSH user myself, and my default scripting language is Python for similar reasons to the OP's for inventing Bish. I can't for the life of me figure out the syntax for an if statement, especially for things like checking if files exist. Yes, Bash or Zsh have a shorter syntax for the example, but to do something like…

I'm with you. I have written a mountain of Bash scripts to solve various one-off problems, and I'm fucked if I can ever remember the nuances from one time to the next -- when to use [], when [[]], when () or (()), when the dollar sign precedes (), etc. Every single time I have to do anything in Bash I have to re-learn Bash. I suppose I keep using it because, even with having to re-learn every single element of Bash c…

My dotfiles[1,2] are full of various functions to do stuff. Half of them I jacked from other people[3] when I was using Bash and ported to ZSH when I discovered Oh-my-zsh. However, a few are my own. The ones that I did write are often one-liners that take an argument and pass it to a series of commands that I'd rather not type. For example history | grep -i command, ls -lah | grep dir, or my favorite, cd dir; ls. If I have to do any logic, aside from determining what OS I'm on, I look to python.

[1] https://github.com/yramagicman/dotfiles [2] https://github.com/yramagicman/zsh-aliases [3] https://github.com/mathiasbynens/dotfiles/blob/master/.funct...

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