How to print hash recursively?

[Peng Yu]

while ( ($k,$v) = each %hash ) {
print "$k => $v\n";
}

The above code would not print the content of $v, if $v points to
complex data structure such as arrays, hash of arrays, etc.

I'm wondering if there is a convenient function that can print a hash
table recursively into the elements.

 

[Jürgen Exner]

while ( ($k,$v) = each %hash ) {
print "$k => $v\n";
}

The above code would not print the content of $v, if $v points to
complex data structure such as arrays, hash of arrays, etc.

I'm wondering if there is a convenient function that can print a hash
table recursively into the elements.

1: it is trivial to write your own
2: Did you check Data:umper?

jue

 

[Peng Yu]

I think you are looking for:

   perldoc Data:umper

If there are many keys in %hash, is there an option in Data:umper so
that only the first a few key value pairs are printed?

 

[sreservoir]

If there are many keys in %hash, is there an option in Data:umper so
that only the first a few key value pairs are printed?

there is no enumeration in a hash

 

[C.DeRykus]

...



If there are many keys in %hash, is there an option in Data:umper so
that only the first a few key value pairs are printed?

I don't know but you could easily partition out a few:

# tie my %hash, 'Tie::IxHash'; # to ensure ordering
# tie my %few, 'Tie::IxHash'; #

@few{(keys %hash)[0..4]}=(values %hash)[0..4]; # dump only 5
print Dumper \%few;

 

[C.DeRykus]

If there are many keys in %hash, is there an option in Data:umper so
that only the first a few key value pairs are printed?

I don't know but you could easily partition out a few:

  # tie my %hash, 'Tie::IxHash';  # to ensure ordering
  # tie my %few, 'Tie::IxHash';   #

  @few{(keys %hash)[0..4]}=(values %hash)[0..4]; # dump only 5
  print Dumper \%few;

For relatively simple hashes only though... more complexity
will probably frustrate attempts at satisfactory partitioning.