On 1/16/01 22:49, Scott R. Godin at [EMAIL PROTECTED] wrote:
> fails:
> my $GameType = param('mapstyle') or $default_mapstyle;
>
> works:
> my $GameType = param('mapstyle') || $default_mapstyle;
According to perlop:
[ ... ]
left ||
[ ... ]
right = += -= *= etc.
[ ... ]
left or xor
In other words, || has a higher precedence than =, which has a higher
precedence than 'or'. So the statement that works parses as
my $GameType = (param('mapstyle') || $default_mapstyle);
which is what you'd expect, but the failing one parses as
(my $GameType = param('mapstyle')) or $default_mapstyle;
which is probably not what you wanted.
> Am I mistaken in assuming that "I should use 'or' because this is 'string
> values'" or does this happen "simply because the possibility of returning
> undef exists in the expression" ?
I think you are mistaken. Are you thinking "'or' for strings" because of
"'eq' for strings"? 'or' vs. || is simply a matter of operator precedence.
--
Craig S. Cottingham
[EMAIL PROTECTED]
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