Your constructor sets time in terms of localtime. Your half-hour calcuation subtracts a half hour from the object that was based on localtime. Your $oldtime object is constructed using strptime, and is not setting a timezone offset.

You can see this in action by adding the following lines: 

print "\$ctime tzoffset:   ", $ctime->tzoffset, "\n";
print "\$halfago tzoffset: ", $halfago->tzoffset, "\n";
print "\$oldtime tzoffset: ", $oldtime->tzoffset, "\n";

[download]

which will produce output along the line of:

$ctime tzoffset:   -25200
$halfago tzoffset: -25200
$oldtime tzoffset: 0

[download]

(...except that the offsets will be in your own localtime, not mine.)

You might be able to set the $oldtime->tzoffset($some_value), or preferably by providing a %Z or %z field to strptime.


Dave

In reply to Re: Simple (I thought) time comparison? by davido
in thread Simple (I thought) time comparison? by sjessie

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