Gregoire Hostettler wrote:
> Hi!
>
> I do not know I am on the right mailing list.
> If not, sorry for the burden.
>
> To say thing briefly:
> I am a programmer for some 25 years using various old and newer
languages.
> I have to write some small things in Perl.
> It was fine and fast with some text analysis.
>
> Now I have to write something using an in-memory "database", i.e. a
SINGLE
> table filled with records.
>
> I am trying to simply add records then retriev them.
> I already spent more than 20 hours for something which should take 30
> minutes....
>
> Seriousely considering making my customer change his mind and revert to
> plain old C++
> Just to be certain not to miss something simple, I attach a small part
of my
> very, very basic trials.
>
> As you can see when running this small piece of "code", as soon as you
push
> a new record, all records already existing become
> filled with the new pushed record and it is impossible to get any
other...
>
> Looks like Perl is not able to handle trivial data structure like an
array
> of records (or hashes).
>
> Thank you for any help!
>
>
> Caracal - G. Hostettler
> 6, ch. du Raidillon
> 1522 Lucens
>
My first bit of advise, don't pass around hashes. Pass references.
Second don't declare the @[EMAIL PROTECTED]
Or rather declare it (with my) but
don't initialize it. The assignment make a great comment, but you don't
declare 'fields' in a hash. On the push in addrec push a reference.
push @[EMAIL PROTECTED]
{ %lrec};
It's just like an array of pointers in C. It an array of hash
references (or pointers).
In getrec, you have an off by 1. $#table is the last used index in
@[EMAIL PROTECTED]
not the size. It's 1 too small. Use scalar(@[EMAIL PROTECTED]
to get the
size or do this
if (($recnum < 0) or ($recnum > ($#table) )) {
To get you hash back you'd need to dereference it.
%lrec = %{$table[$recnum]}
Your statements to print the size should look more like:
print "Added rec. tblsize = ", scalar(@[EMAIL PROTECTED]
), "\n";
After all of this, you code is still going to be kind of ugly because
you pass around the hash in list context.
try something like
sub addrec { # takes a list of key value pairs
push @[EMAIL PROTECTED]
{ @[EMAIL PROTECTED]
}
}
getrec($){ # take an index, returns hash ref or undef on failure
return $table[****ft]; # gets undef() on failure
}
Dan
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