> [EMAIL PROTECTED] wrote:
>
> > Hi All
> >
> >Prob: I want to convert all the elememts of an array to ascalor variable tha
> t I can use latter on in my code
> >e.g.
> >
> >my @array=qw/balli johney bobby/;
> >now here i need 3 different variable with the above values i.e.
> >my $name1=balli ;
> >my $name2=johney ;
> >my $name3=bobby ;
> >
> >Soln so far:
> >
> >my ($i) ;
> >for ($i=0; $i<@array;$i++)
> >{
> >$name=$array[$i] ; # lost here is to how to have different $name each time a
> lso how can make these
> >
> my $i;
> for ($i=0; $i<@arrayl $i++) {
> $name$i=$array[$i];
> }
>
> That way you don't need to know in advance how many $name variables you
> need.
>
NO, NO, NO, NO, NO!!!!!!!!!!!!!!!!!
First: Your code doesn't even work.
Second: It is not actually SOLVING anything.
variables of the form
$name0, $name1, $name2
... do not provide **ANY** functional difference from
$array[0], $array[1], and $array[2]
Write that on the blackboard fifty times.
That is to say: $array[0] is a first-class citizen, just as good as
$name0 -- iterating in the worst possible way[1] across an array to
create copies of the data provides NO additional functionality to the
code.
I suspect if the original poster could read and write English he
(she?) would be able to explain what was really needed.
There *are* times when exploding an array into a series of separately
named scalars *does* make sense.
Think how stupid the following is:
my @array;
($array[0], $array[1], $array[2], $array[3],
$array[4], $array[5], $array[6], $array[7], $array[8] ) = localtime(time);
But, if we rewrite it thusly...
my ($second, $minute, $hour,
$month_day, $month, $year,
$weekday, $yearday, $isdst ) = localtime(time);
...the phrase makes sense. You are expanding the list of nine data
returned by localtime into convenient mnemonic variables.
(Getting further afield: I would probably never do THAT either -- if I
have a series of nine things that are tightly coupled, I would want
some better data structure to hold them. A hash or hashref, would be
perfect.)
my $localtime;
@$localtime{qw / second minute hour mday month year weekday yearday isdst /} =
localtime(time);
[1] A style nit:
Write Perl, not C.
If you DO need to iterate across all the indices for an array ( rarely
necessary if you have designed your data correctly ) do it right:
my @person = ( qw / Freddy Mary Georgetta Loretta Fred Lawrence / );
##
## UNBEARABLY LAME C
##
for ( my $index = 0 ; $index < @person ; $index ++ ) {
print "unbearably bad $person[$index]\n";
}
##
## MERELY BAD PERL
##
for my $index ( 0 .. $#person ) {
print "merely bad $person[$index]\n";
}
##
## GETTING INTO THE PERL STATE OF MIND
##
for my $person (@person) {
print "Hello $person\n";
}
Note that of the three techniques, the last is the only one that will
work for all values of $[ (of course, anyone who sets $[ to any
nonzero value deserves hot pokers in the eyes.)
-- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
Lawrence Statton - [EMAIL PROTECTED] s/aba/c/g
Computer software consists of only two components: ones and
zeros, in roughly equal proportions. All that is required is to
sort them into the correct order.
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