Bug #2709: $VERBOSE, $DEBUG and Kernel#sprintf
http://redmine.ruby-lang.org/issues/show/2709

Author: Patrik Wenger
Status: Open, Priority: Low
Category: core
ruby -v: ruby 1.9.1p376 (2009-12-07 revision 26041) [x86_64-linux]

Kernel#sprintf is very useful. I think the power lies within the ignorance of too many arguments. So one is free to decide which arguments he uses and which one he doesn't. This applies to a Ruby runtime where $VERBOSE and $DEBUG are false.

Following the POLS (Principle of the least surprise), one would assume that changing the variables $VERBOSE and $DEBUG wouldn't change the behavior of Kernel#sprintf. But they do.

$VERBOSE causes warnings when there are too many arguments.
$DEBUG causes an ArgumentError when there are too many arguments. This isn't useful at all.

I like the effect of $DEBUG according to threads, to raise uncaught exceptions from the thread.
But in the case of Kernel#sprintf, it's just not useful. This behavior prohibits some power of Ruby.

My suggestion:
Remove the special behavior of $VERBOSE and $DEBUG in Kernel#sprintf.

Thank you very much.


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