Re^2: [ DateTime::Duration ] off by one problem with negative seconds

Many thanks a +0 to explicitly convert to number is fixing the issue.

> If I were to supply a value for nano- or microsecond, I would have thought that an integer would have been sufficient, and not to have supply a string for the value.

The string is an artefact from an sprintf to convert non-nanos to nanos.

> All of the numbers must be integers.

It's Perl's dogma to treat all convertible scalars alike, including integers and strings of integers.

  DB<75> use warnings; print "001"+"001"     # no warnings
2
  DB<76>
[download]

I read the docs as "don't pass real numbers".

Keep in mind that the nanosecs could have been read from a file and come as string inside a variable.

DT::D only fails in this special case and I suppose it's because there is an inner test for falseness to see if the nanosecs are 0 ... but "000000000" OTOH is true.

some minutes later

My Boolean theory seems to be right, passing "0" works fine (false), but "00" fails (true).

Cheers Rolf
_{(addicted to the Perl Programming Language :)

Wikisyntax for the Monastery
FootballPerl is like chess, only without the dice}

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Re^3: [ DateTime::Duration ] off by one problem with negative seconds by LanX (Saint) on Dec 28, 2019 at 03:58 UTC
> I suppose it's because there is an inner test for falseness to see if the nanosecs are 0 ... but "000000000" OTOH is true. found the problem in the constructor `if ( $p{nanoseconds} ) { # <-- +0 sho +uld fix it $self->{nanoseconds} = $p{nanoseconds}; $self->_normalize_nanoseconds; } else { # shortcut - if they don't need nanoseconds $self->{nanoseconds} = 0; } ... # and later # make the signs of seconds, nanos the same; 0 < abs(nanos) < MAX_NANO +S # NB this requires nanoseconds != 0 (callers check this already) # <- +- GOTCHA! sub _normalize_nanoseconds { ...` [download] Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}	[reply] [d/l]

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Re^3: [ DateTime::Duration ] off by one problem with negative seconds
by LanX (Saint) on Dec 28, 2019 at 03:58 UTC

> I suppose it's because there is an inner test for falseness to see if the nanosecs are 0 ... but "000000000" OTOH is true.

found the problem in the constructor

        if ( $p{nanoseconds} ) {                          # <-- +0 sho
+uld fix it
            $self->{nanoseconds} = $p{nanoseconds};
            $self->_normalize_nanoseconds;
        }
        else {
 
            # shortcut - if they don't need nanoseconds
            $self->{nanoseconds} = 0;
        }


... # and later

# make the signs of seconds, nanos the same; 0 < abs(nanos) < MAX_NANO
+S
# NB this requires nanoseconds != 0 (callers check this already)  # <-
+- GOTCHA!
sub _normalize_nanoseconds {

...
[download]

Cheers Rolf
_{(addicted to the Perl Programming Language :)

Wikisyntax for the Monastery
FootballPerl is like chess, only without the dice}

[reply]
[d/l]