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Postings from April 2010
On Thu, Apr 15, 2010 at 10:55 AM, Uri Guttman <uri@stemsystems.com> wrote:
> >>>>> "r" == raphael() <raphael.japh@gmail.com> writes:
>
> r> # abc <-- this_should_be_hash_name
>
> r> {space} "random_name_or_number" "date" "other_things_1"
> "other_things_2"
> r> {space} "random_name_or_number" "date" "other_things_1"
> "other_things_2"
>
> r> How can I create a hash by the name that matches
>
> r> m/^#(?:\s+)?(\S+)$/
>
> r> The hash should be created by the name of "$1" i.e (\S+)$
> r> like if "$1" is 'abc' the hash should be %abc which will later be
> filled by
> r> keys & values
> r> that are matched in the next line. Thus hash should be created
> beforehand.
>
> this is called symbolic references and it is a very bad
> idea. effectively you would be using perl's symbol table as a data
> structure which gains nothing, can cause major problems (everything is
> global), and can also slow you down.
>
> the proper solution is to use a hash to hold these hashes. this is
> cleaner, safer, allows you to isolate this data, pass it around easily,
> reclaim its memory when it is not being used anymore, etc.
>
> notice how many bad things there are about symbolic references and how
> many good things about multilevel hashes? also note that symrefs are not
> allowed under strict (which you should be using all the time).
>
> so just declare a top level hash like this:
>
> my %top_data ; # pick a better name
>
> and then just assign into it the data you want with an anonymous hash:
>
> $top_data{ $1 } = { $2 => $3 } ;
>
> or use whatever regex grabs you want.
>
> read these docs for more on this:
>
> perlreftut
> perldsc
> perllol
>
> uri
>
> --
> Uri Guttman ------ uri@stemsystems.com -------- http://www.sysarch.com--
> ----- Perl Code Review , Architecture, Development, Training, Support
> ------
> --------- Gourmet Hot Cocoa Mix ---- http://bestfriendscocoa.com---------
>
You are right!
But as a beginning Perl programmer I find references extremely complicated.
Although I have to learn them sometime.
Going to code now. Will be back if I get stuck && *thanks* all.
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