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Comment by phinnaeus | Hacker News Reader

I do really like the implementation of help text:

    function bocker_help() { #HELP Display this message:\nBOCKER help
     sed -n "s/^.*#HELP\\s//p;" < "$1" | sed "s/\\\\n/\n\t/g;s/$/\n/;s!BOCKER!${1/!/\\!}!g"
    }

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Initially I thought that bash supports reflection and is able to get the function contents, including comments. But this function scans its own script file ($1), looking for the comments starting with #HELP and formatting them. This way the usage info can live near the functions implementing sub-commands.

Yup. It is a nice trick that you might find more often in Makefile. I have a make target that does this consistently in all the makefiles I write: https://github.com/andreineculau/core.inc.mk/blob/master/tar...

  target1: ## Do this
  target2:
  target3: target2 ## Do that

would be nicely formatted as the output of `make help` into

  Available targets:
    target1  Do this
    target2  Do that

and if you want to see all targets along with their origin file, even those without help messages, type `make help-all` to render

  Available targets:
    target1  path/to/Makefile  Do this
    target2  path/to/Makefile
    target3  path/to/Makefile  Do that

> Initially I thought that bash supports reflection ... But this function scans its own script file

That certainly counts as reflection in the context of shell scripting... :-P

It'd be even better if the help texts would be readable in the source, but that would cost some lines for sure

What do you mean? They are in the source.

Do you just mean without the escaped newline characters? Because the fact that they serve as function comments is exactly what I found to be novel about it.

I like the idea too but just the thought of needing to go through those text blocks to edit them makes me sad

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