# Re: Ruby idiom equivalent to Perl "$asdf = $ARGV|| die 'arg required'"?\]

**URL:** <https://www.ruby-forum.com/t/re-ruby-idiom-equivalent-to-perl-asdf-argv-die-arg-required/122058>\
**Category:** Ruby\
**Created:** [December 4, 2007, 8:31am UTC](https://www.ruby-forum.com/t/re-ruby-idiom-equivalent-to-perl-asdf-argv-die-arg-required/122058 "2007-12-04T08:31:18Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![curt\_s](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/b77776/32.png) [@curt\_s](https://www.ruby-forum.com/u/curt_s)\
**Post date:** [December 4, 2007, 8:31am UTC](https://www.ruby-forum.com/t/re-ruby-idiom-equivalent-to-perl-asdf-argv-die-arg-required/122058/1 "2007-12-04T08:31:18Z")

</div>

Something like this, perhaps?

```
a = ARGV[0] || fail('arg required')

```

cjs

---

<div class="post-metadata">

**Author:** ![curt\_s](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/b77776/32.png) [@curt\_s](https://www.ruby-forum.com/u/curt_s)\
**Post date:** [December 4, 2007, 9:05am UTC](https://www.ruby-forum.com/t/re-ruby-idiom-equivalent-to-perl-asdf-argv-die-arg-required/122058/2 "2007-12-04T09:05:54Z")

</div>

2007/12/4, Curt S. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid):

> Something like this, perhaps?
> 
> ```
> a = ARGV[0] || fail('arg required')
> 
> ```

Here’s some more

a = ARGV.shift or raise “arg required”  
a = ARGV.shift or raise ArgumentError, “arg required”

For more complex cmd line parsing I’d use OptionParser.

Kind regards

robert