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There's not much you can do in Awk that you can't do elsewhere: Turing-completeness and all that. The reverse also applies, assuming you have an appropriate set

There's not much you can do in Awk that you can't do elsewhere: Turing-completeness and all that. The reverse also applies, assuming you have an appropriate set of bindings. The thing to understand about awk is that it's basically a DSL. It's optimized specifically for crunching data contained in line-oriented text files, and within this niche, it is awesome. Since line-oriented text files are used for just about everything in Unix, awk is an especially useful tool there. But once you stray from awk's niche, things start to get awkward, and the further you go, the tougher it gets. Perl was written to be an awk-killer, and it didn't accomplish that by being better within awk's niche. It did it by not being a DSL: it's still "good enough" for the sorts of work that awk really excels at, but it works much better for just about everything else.

kenko 13y ago
"There's not much you can do in Awk that you can't do elsewhere: Turing-completeness and all that." The fact that Awk is Turing-complete has nothing to do with the fact (if it is a fact) that there's not much you can do in it that you can't do elsewhere. The SKI combinator calculus is Turing-complete, but you can't read a CSV file with it.
- throwaway1980 13y ago
  > The SKI combinator calculus is Turing-complete, but you can't read a CSV file with it. Of course you can, it's just a matter of input handling. For that matter you can read a CSV file with any Turing machine. It's just easier elsewhere.
  - kenko 13y ago
    Well, I must be very confused, then, because I don't see where the input comes in given just the s, k and i combinators. (The Jot programming language, which can be translated into SKI, for instance, doesn't do input or output. You want the Zot variant for that.) How would one write a program, using just s, k, i, and application, that takes the name of a file on the command line, opens it and reads it in, then prints the lines in reverse order to stdout?
    - Millennium 13y ago
      If you really wanted to do pure SKI, you'd have to do more than just a program: you'd have to implement the whole machine and the OS running on it. You could do that, but as you might imagine, it's quite a lot of work. That said, keep in mind that most likely, you'd want to start implementing levels of abstraction pretty early on. The fact that SKI is Turing-equivalent means that you can implement a Turing machine (or anything else that is Turing-equivalent) in it. Build your favorite abstraction, and then implement your machine and OS the way you would using that abstraction. It's still SKI underneath, so you're golden.
      - innguest 13y ago
        I don't understand how your reply addresses anything kenko said. I agree with kenko and I wish people would stop bringing turing completeness/equivalence into discussions about what languages can do what. Turing completeness is inconsequential in such discussions; we're talking about what's practical and reasonable to do in each language. I wish people would stop trying to impress us with academic tangents.
        Millennium 13y ago
        The site's called Hacker News for a reason, and it caters to entrepreneurs for the same reason. We're already people with something of a penchant for not caring about the "practical" or "reasonable," or even considering that to be a challenge. But if we're going to talk about what is practical and reasonable, then let's look back at awk's niche: prying data out of line-oriented text files. For that particular task, C and the basic lisps rank among my languages of last resort: assembler (pick an architecture) would be worse, but that's just about it. There are libraries for these languages which would help significantly, but my awk script would be finished and halfway through the dataset by the time I even got the build environment set up for these languages, and the code would still be more clear. Like I said, the right tool for the job. For many tasks -most, actually- awk would not be very high on my list of languages to try. But find a task that hits awk's sweet spot, and nothing beats it.
      - kenko 13y ago

kenko 13y ago

"There's not much you can do in Awk that you can't do elsewhere: Turing-completeness and all that." The fact that Awk is Turing-complete has nothing to do with the fact (if it is a fact) that there's not much you can do in it that you can't do elsewhere. The SKI combinator calculus is Turing-complete, but you can't read a CSV file with it.

throwaway1980 13y ago
> The SKI combinator calculus is Turing-complete, but you can't read a CSV file with it. Of course you can, it's just a matter of input handling. For that matter you can read a CSV file with any Turing machine. It's just easier elsewhere.
- kenko 13y ago
  Well, I must be very confused, then, because I don't see where the input comes in given just the s, k and i combinators. (The Jot programming language, which can be translated into SKI, for instance, doesn't do input or output. You want the Zot variant for that.) How would one write a program, using just s, k, i, and application, that takes the name of a file on the command line, opens it and reads it in, then prints the lines in reverse order to stdout?
  - Millennium 13y ago
    If you really wanted to do pure SKI, you'd have to do more than just a program: you'd have to implement the whole machine and the OS running on it. You could do that, but as you might imagine, it's quite a lot of work. That said, keep in mind that most likely, you'd want to start implementing levels of abstraction pretty early on. The fact that SKI is Turing-equivalent means that you can implement a Turing machine (or anything else that is Turing-equivalent) in it. Build your favorite abstraction, and then implement your machine and OS the way you would using that abstraction. It's still SKI underneath, so you're golden.
    - innguest 13y ago
      I don't understand how your reply addresses anything kenko said. I agree with kenko and I wish people would stop bringing turing completeness/equivalence into discussions about what languages can do what. Turing completeness is inconsequential in such discussions; we're talking about what's practical and reasonable to do in each language. I wish people would stop trying to impress us with academic tangents.
      - Millennium 13y ago
        The site's called Hacker News for a reason, and it caters to entrepreneurs for the same reason. We're already people with something of a penchant for not caring about the "practical" or "reasonable," or even considering that to be a challenge. But if we're going to talk about what is practical and reasonable, then let's look back at awk's niche: prying data out of line-oriented text files. For that particular task, C and the basic lisps rank among my languages of last resort: assembler (pick an architecture) would be worse, but that's just about it. There are libraries for these languages which would help significantly, but my awk script would be finished and halfway through the dataset by the time I even got the build environment set up for these languages, and the code would still be more clear. Like I said, the right tool for the job. For many tasks -most, actually- awk would not be very high on my list of languages to try. But find a task that hits awk's sweet spot, and nothing beats it.
    - kenko 13y ago