[nycbug-talk] nifty(1)

William Baxter web-nycbug at superscript.com
Thu Dec 15 21:24:56 EST 2011

Excerpts from Matthew Story's message of Thu Dec 15 00:54:24 -0500 2011:
> i believe the most portable version is slightly uglier:
> On Dec 14, 2011, at 6:13 PM, Isaac Levy wrote:
> >  shout() { echo "$0: $*" >&2; }
> >  barf() { shout "$*"; exit 111; }
> safe() { ${1+"$@"} || barf "cannot $*"; }
>           ^^^^^^^^ this bit is more reliable for sh on Solaris (real Bourne shell)

Delightful as the topic of Solaris compatibility may be I don't think it's worth
going that far.  The ${1+"$@"} construct is indispensable for compatibility in
cases when an empty list is legitimate while an unintended empty argument is

  for ${1+"$@"}


  for "$@"

But an empty string and an empty list are both erroneous for safe().  While the
execution details may vary from shell to shell, I consider it a case of pilot
error to pass in either an empty argument or no argument to a function that
requires a program.  A function cannot ultimately protect the caller from his
own error.

Cheers, W.

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