Empty string is False right?

Steve Holden steve at holdenweb.com
Sat Jan 31 14:27:20 CET 2009

AJ Ostergaard wrote:
> I'm not suggesting it's not operating as advertised - I'm suggesting the
> 'advertising' is slightly sguiffy if you catch my drift. I guess it's
> just me that finds it slightly counter intuitive. Surely intuitively the
> expression is "and" and therefore should always return a boolean?
> I'll shut up now. ;)
You might think so, and it wouldn't be an entirely unreasonable thought,
but in practice it makes a lot of sense to retain the original value
where possible.

The fact is that any left-hand operand that evaluates to false in a
Boolean context can be used as it stands rather than being converted to
Boolean first. So the conversion is essentially useless processing.

Steve Holden        +1 571 484 6266   +1 800 494 3119
Holden Web LLC              http://www.holdenweb.com/

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