Comment by neuromanser | Hacker News Reader

Comment by neuromanser | Hacker News Reader

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> Heh, was that an attempt at sarcasm?

There was definitely a wink component, but at the same time, I meant it.

Half the code is just case / esac syntax, which you can (i do) find plenty use for outside of getopts. getopts itself is… manageable. In the end, the code is such a strong pattern, it's basically a snippet. The lack of variation is what makes it kinda easy to remember. Or you could put it in your notes or a gist and copy/paste.

> That's super difficult to do from memory, at least for me. Maybe I'm not as good at memorizing things as you are.

Nah, my memory is shot. It's a matter of practice, and not being shy with man pages. Use it often enough, it's in memory; after a long hiatus, the details are a "/^\s*getopts \[" away (assuming your man pager is less).

I find it's much better to have a copy-pasted piece of code which turns all command line options into variables in a certain namespace (provided the variables are defined beforehand)

I.e. user runs:

  script --foo --bar=yes --no-xyzzy --uiuez"

the script then sets these existing variables:

  opt_foo=y
  opt_foo_given=y

  opt_bar=y
  opt_bar_given=y

  opt_xyzzy=
  opt_xyzzy_given=y

However, the variable opt_uiuez doesn't exist and so it bails:

  script: no such option: --uiuez

With such a piece of code, all you do is define the options you support via assignments like "opt_foo=". You can give them default values this way. Include that piece of boiler-plate code. Done.

To add a new option, just define the variable. Done.

Check its value wherever needed, and possibly the _given, if the code needs to know whether it's working with the default value, or an explicitly given value. That's it.

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