in reply to Conditionally override 'time' builtin with Time::HiRes::time()

#!/usr/bin/perl

use strict;

BEGIN {
  our $phase_of_moon = shift || int(rand(100));
}

use if $::phase_of_moon > 42, 'Time::HiRes' => qw( time );

my $foo = time;
print $foo, "\n";

__END__

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Re: Re: Conditionally override 'time' builtin with Time::HiRes::time()
by chip (Curate) on Apr 30, 2004 at 00:29 UTC
    Nice use of if.pm, Fletch, but points off for unnecessary package variable. 

    my $phase;
BEGIN { $phase = shift || int(rand 100) }
use if $phase > 42, Time::Hires => qw( time );

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        -- Chip Salzenberg, Free-Floating Agent of Chaos

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Re: Re: Conditionally override 'time' builtin with Time::HiRes::time()
by meonkeys (Chaplain) on Apr 30, 2004 at 00:29 UTC

    Ah, perfect!

    Here's what I really want, though: 

    #!/usr/bin/perl -w
use strict;

BEGIN {
  Time::HiRes->import('time') if eval "require Time::HiRes";
}

my $time = time;
print "$time\n";

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    UPDATE (Fri Apr 30 11:15:23 PDT 2004):

    Your advice is well-received, chip! Changed the eval EXPR to eval BLOCK. As for letting the user know, that is also a good idea. I left that out for brevity. This is actually for a patch to Net::IRC, so I'll let Jeremy (the maintainer) decide weather he wants to emit a warning. 

    #!/usr/bin/perl -w
use strict;

BEGIN {
  Time::HiRes->import('time') if eval { require Time::HiRes };
}

my $time = time;
print "$time\n";

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    ---
    "A Jedi uses the Force for knowledge and defense, never for attack."
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      That eval STRING could just as well be eval BLOCK.

      More to the point: Having your program work differently just because a module gets installed is usually evil. People don't expect that installing a module will make apparently unrelated code start doing different things. At least print a diagnostic or something, a la CPAN and Term::ReadLine.

          -- Chip Salzenberg, Free-Floating Agent of Chaos

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