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Comment by Animats | Hacker News Reader

There was a time (PWB Research Unix) when one typed:

    ls | sort | mc

to get an alphabetical list in multiple columns. That didn't last.

This reads like someone discovered functional programming and now wants everything to be functional.

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Isn't that kinda the point? Why would that be a bad thing? Seemingly, my version of ls doesn't provide a 'sort alphabetically' flag, but if it did, the equivalent of

    ls | sort | mc

would be something like

    ls -C --sort=name

and, as discussed, the ls program has to be much, much more complicated.

UNIX pipeline data is mostly raw strings. To do anything non-trivial, you have to know the format of the previous pipeline item and have a parser for it. It would be amusing to have a system where all commands output JSON, so that pipelined programs can process the previous input. Then you could have

    ls | sort --key=modification_time | mc

For display, you'd have a convention that if there's a "text" field in the JSON, that's what's displayed in the console window. Otherwise you see the raw JSON. So "ls" would output an array of JSON records with all the usual fields, but if you just wrote

ls

the user would see a list of file names.

You could have "format" and "select" programs:

    ls | select --exclude="owner=root" | sort --key=modification_time | format  
        --fields=name,modification_time,size

This would be quite powerful and would allow the creation of complex, functional pipelines. The end result is basically equivalent to SQL, but it's functional!

This was the point of Powershell, where programs pass around objects, rather than plain text: https://en.wikipedia.org/wiki/PowerShell#Pipeline

Cute. So, while Unix is not an acceptable Unix, maybe Windows now is.

Plan 9's 'ls' still behaves in the old fashion, and if you want it formatted nicely you run 'lc', which is just a shell script that does ls | mc

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