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how to have hash of list in perl

Sorry for this syntax question. I fail to find the solution. I开发者_开发技巧 want to have an array of hashs in perl, each of them has string and array. I'm trying to write the following code:

use strict;
my @arr = (
       { name => "aaa" , values => ("a1","a2") },
       { name => "bbb" , values => ("b1","b2","b3") }
      );


foreach $a (@arr) {
  my @cur_values = @{$a->{values}};
  print("values of $a->{name} = @cur_values\n");
};

But this does not work for me. I get compilation error and warning (using perl -w)

Odd number of elements in anonymous hash at a.pl line 2. Can't use string ("a1") as an ARRAY ref while "strict refs" in use at a.pl line 9.


I want to have an array of hashs in perl

You can't. Arrays only contain scalars in Perl. However, {} will create a hashref, which is a scalar and is fine.

But this:

{ name => "aaa" , values => ("a1","a2") }

means the same as:

{ name => "aaa" , values => "a1", "a2" },

You want an arrayref (which is a scalar), not a list for the value.

{ name => "aaa" , values => ["a1","a2"] }


Try the following:

use strict;
my @arr = (
       { name => "aaa" , values => ["a1","a2"] },
       { name => "bbb" , values => ["b1","b2","b3"] }
      );


foreach $a (@arr) {
  my @cur_values = @{$a->{values}};
  print("values of $a->{name}: ");
    foreach $b (@cur_values){
        print $b . ", "
    }
    print "\n";
};

You just needed to use square brackets when defining your array on lines 3 and 4.


my @arr = (
            { name => "aaa" , values => ["a1","a2"]      },
            { name => "bbb" , values => ["b1","b2","b3"] }
          );

Lists ( made with ()) will get flattened. Arrayrefs ([]) won't.

See perldoc perlreftut for more.

Also, avoid using $a and $b as variable names as they are intended for special use inside sort blocks.

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