my ($a, $b, $c) = ('TRUE') x 3;
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Always many ways of doing it ;-)

This solution is less good than simply assigning the value to each variable separately in my $a = my $b = my $c = 'TRUE' because it avoids having to count how many variables you have. In your code, if you got the number wrong then the trailing variables will be left undefined which is far and away from the intent to leave them with a true value. You're making it easy to write in a bug later.

Good point. One could always do this:

use Want 'howmany';
my ($a, $b, $c) = &{ sub{ (1) x howmany } };
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Not sure if that's shorter/better than other solutions (plus requires Want), but it's another way of keeping the number of variables in sync.

-xdg

Code written by xdg and posted on PerlMonks is public domain. It is provided as is with no warranties, express or implied, of any kind. Posted code may not have been tested. Use of posted code is at your own risk.

Jeepers! the 'x' operator works on lists too!?

Looks like time to refactor out all ...

my ($a,$b,$c) = map {'TRUE'}(0 .. 2);
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Yep, it does. Note the difference between these, though:

$,= " "; $\ = "\n";
print( map { int rand 10 } 0 .. 6 );
print( ( int rand 10 ) x 7 );
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The x operator only evaluates the list expression once. So you can't always substitute one for the other.

Makeshifts last the longest.

scooterm,
Not only that, but if the what the list contains is a reference, the reference is replicated as well. The first useful application I remember seeing of this is in tye's Algorithm::Loops. I found a useful variation that looked a little something like:

my @signal = qw(ABRT STOP TERM INT);
@SIG{ @signal } = (sub { kill 9, $pid; exit }) x @signal;
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Incidently, diotalevi makes a good point concerning ensuring that you have the same number of things on both sides of the assignment which is not an issue in my example.

Cheers - L~R

my $a = my $b = my $c = "TRUE";
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my $a = 
my $b = 
my $c = "TRUE";
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For comleteness' sake, you can also do the following:

$_ = "TRUE" for my ( $a, $b, $c );
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That my declaration is actually not restricted to the loop, the variables are available down the block this statement appears in. That will probably surprise most readers of your code, though, so you don't actually want to use it in practice.

Makeshifts last the longest.

That hurts my head just to look at! I hope the retribution of the gods for writing it was swift and just! *grin*

--
Do not seek to follow in the footsteps of the wise. Seek what they sought. -Basho

Others have told you how to do what you ask but I'd like to point out that at least 90% of the time when people think they want declare three or more scalars in the same place and assign then all the the same value they are wrong.

Usually they are making one or more of the following mistakes:

• Suffering from premature declaration. (i.e. not declaring all variables in the smallest applicable scope).
• Using multiple scalar variables where they should be using a hash or array.
• Representing the concept of undefindness using some value other than undef.

Here's another variation on a theme:

map{ $_ = 'TRUE' }
    my( $a, $b, $c );
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Not sure if that's taking us farther down an obfuscated road, but it does wield map in void context for the fun of it. ;)

I've noticed that

my ($a,$b,$c) = "TRUE";

doesn't work

my @badger="true";
foreach (@badger){print "$_\n"}
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The following

my ($a,$b,$c) = ("TRUE", "TRUE", "TRUE");
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works OK, because the variables on both side of the '=' are arrays - note the ()

Note that I'm not advocating using this last syntax. I agree with diotalevi that it potentially introduces a bug if you don't use enough "TRUE" values. Personally, I favour jdporters syntax, I'm just pointing out why your original failed.

They're lists, not arrays. It's an important distinction; try a list of different elements versus an array of different elements assigned to lists and scalars on the left hand side with and without parenthesis.

In general saying "it doesn't work" is not helpful. It's better to say "it doesn't do what I expected, and I expected it to do $foo".

The OP said, "I want to do X, but when I try Y, it doesn't work." Now you're saying that Y does work. But you've taken it out of the context of the stated need, X.

Hi, Just try this it's easy method

$a = $b = $c = "True";
print "\n$a$b$c";
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The OP wanted to declare the three variables my.