I have a variable which should be any number between 1 and 50.
It could also be any string/empty string.
I have a code written below. The point is when the variable contains string.
I don't want the code below to error out. Instead fall in the else bucket.
How can I test a variable to see if its in the right format?
The format for the variable would be 'DDMMYYYY HH:MM:SS' and is passed from a command line argument.
Any help would be appreciated (2 Replies)
hi forum
i beginning with script and i want test un null variable in a schell
i just don t know the syntax here is a litle example
y=test
echo $y
unset y
echo $y (so here Y = Null)
if Y=Null
then
echo "y is null"
exit
fi (1 Reply)
I'm using the following line in bash to test whether an argument supplied is an absolute path or not:
if echo $1 | grep '^/' > /dev/null
then
absolute=1
else
absoute=0
fi
The line appears to work but seems somewhat unprofessional looking to me. Is it an acceptable... (2 Replies)
hi,
i store a constant in a variable and want to test whether it is M or Z.
how can i achieve this?? please help
variable='M'
if
then
ehco 'success'
fi;
is this right ?? (2 Replies)
I'm trying to test and see whether a variable that is being extracted from a line in a file is numeric or not. I have tried everything that I can think of and I cannot figure out how to get it to work. I am trying to test and see if the string extracted contains 5 numeric digits. This is what I... (8 Replies)
This is the code:
while test 1 -eq 1
do
read a
$a
if test $a = stop
then
break
fi
done
I read a command on every loop an execute it.
I check if the string equals the word stop to end the loop,but it say that I gave too many arguments to test.
For example echo hello.
Now the... (1 Reply)
Hello, Unix-forums!
My problem:
read -p "Enter any number, please" number
sleep 1
echo $number | tr -d 0-9
test -z $number && echo "Thank you" || echo "This is not a number"Test always displays "This is not a number". It doesn't matter if I entered a or 1.
But if I order
echo... (2 Replies)
Hi,
I am trying to get the oracle variables and pass the values in sql placed in procedure.
VARIABLE
vstat='ASDS,FGDS,VCGD,VCXC'
Query :
select distinct dept from College
where section in ('C','D')
AND CODES =''
AND NAMES IN ('RAJ','SAM');
I want CODES values to be taken from vstat... (1 Reply)
Hello,
I have two files, f1 and f2. f1 has 5 columns like so:
a b c d 154
e f g h 365
.....
f2 has two columns, the first column contains the name of the above file and second column contains a constant which is to be used for division.
e.g.
file1 56
I want to divide the 5th... (2 Replies)
Discussion started by: Gussifinknottle
2 Replies
LEARN ABOUT DEBIAN
devel::refcount
Devel::Refcount(3pm) User Contributed Perl Documentation Devel::Refcount(3pm)NAME
"Devel::Refcount" - obtain the REFCNT value of a referent
SYNOPSIS
use Devel::Refcount qw( refcount );
my $anon = [];
print "Anon ARRAY $anon has " . refcount($anon) . " reference
";
my $otherref = $anon;
print "Anon ARRAY $anon now has " . refcount($anon) . " references
";
DESCRIPTION
This module provides a single function which obtains the reference count of the object being pointed to by the passed reference value.
FUNCTIONS
$count = refcount($ref)
Returns the reference count of the object being pointed to by $ref.
COMPARISON WITH SvREFCNT
This function differs from "Devel::Peek::SvREFCNT" in that SvREFCNT() gives the reference count of the SV object itself that it is passed,
whereas refcount() gives the count of the object being pointed to. This allows it to give the count of any referent (i.e. ARRAY, HASH,
CODE, GLOB and Regexp types) as well.
Consider the following example program:
use Devel::Peek qw( SvREFCNT );
use Devel::Refcount qw( refcount );
sub printcount
{
my $name = shift;
printf "%30s has SvREFCNT=%d, refcount=%d
",
$name, SvREFCNT($_[0]), refcount($_[0]);
}
my $var = [];
printcount 'Initially, $var', $var;
my $othervar = $var;
printcount 'Before CODE ref, $var', $var;
printcount '$othervar', $othervar;
my $code = sub { undef $var };
printcount 'After CODE ref, $var', $var;
printcount '$othervar', $othervar;
This produces the output
Initially, $var has SvREFCNT=1, refcount=1
Before CODE ref, $var has SvREFCNT=1, refcount=2
$othervar has SvREFCNT=1, refcount=2
After CODE ref, $var has SvREFCNT=2, refcount=2
$othervar has SvREFCNT=1, refcount=2
Here, we see that SvREFCNT() counts the number of references to the SV object passed in as the scalar value - the $var or $othervar
respectively, whereas refcount() counts the number of reference values that point to the referent object - the anonymous ARRAY in this
case.
Before the CODE reference is constructed, both $var and $othervar have SvREFCNT() of 1, as they exist only in the current lexical pad. The
anonymous ARRAY has a refcount() of 2, because both $var and $othervar store a reference to it.
After the CODE reference is constructed, the $var variable now has an SvREFCNT() of 2, because it also appears in the lexical pad for the
new anonymous CODE block.
PURE-PERL FALLBACK
An XS implementation of this function is provided, and is used by default. If the XS library cannot be loaded, a fallback implementation in
pure perl using the "B" module is used instead. This will behave identically, but is much slower.
Rate pp xs
pp 225985/s -- -66%
xs 669570/s 196% --
SEE ALSO
o Test::Refcount - assert reference counts on objects
AUTHOR
Paul Evans <leonerd@leonerd.org.uk>
perl v5.14.2 2011-11-15 Devel::Refcount(3pm)