The shok command shell

Re:The shok command shell by MatmaRex on Sunday December 29, 2013 @06:52AM (#6979313)

map, fold and filter can approximate the pipeline pretty well. Personally I only use shell scripting when I actually want to record a set of commands I ran (or, well, when working in a shell); in all other cases I whip out proper tools.

Here's a comparison of code to do the same thing written in Ruby:

    Dir['**/*.py'].map{|f| File.readlines(f).length }.inject(:+)
    find . -name '*.py' | xargs cat | wc -l

That's 60 characters versus 39 (most of these are just because the "commands" are longer – and I don't think anyone would even try to argue that 'cat' or 'wc' is more readable than 'File.readlines' or 'length').

I ran them on Python 2.7's library directory and my version counted four lines more – I didn't investigate, but I think yours missed lines when cating files without trailing newline. I'd argue that's a bug in your code :)

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Re:The shok command shell by xiaq on Sunday December 29, 2013 @07:13AM (#6979343)

Though it's mostly a matter of taste, I find pipelines simpler and more natural than method calls. Compare:

    xs.filter(p).map(f)

with

    filter p xs | map f

(Suppose filter and map are implemented such that they accept input either on the command line or from pipeline.)

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Re:The shok command shell by Tyr42 on Sunday December 29, 2013 @09:16AM (#6979571)

Well, lets try Haskell syntax

    map f $ filter p xs

what, don't like the reverse order? That's fixable. If we define # as reverse function application, it's

    xs # filter p # map f

    filter p xs # map f

which is quite similar to what you are looking for.

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