I have a HoL with data in it (lists of hashrefs, as it happens). But, I want to filter some of the lists that are in the top-level hash keys, leaving others keys intact. I did this, and put the altered keys (the lists) into a new HoL, naively thinking I could assign them back like this:


#This bit works
foreach (@{$row_data{groups}}){ push @{$new_row_data{groups}}, $_ if $
+{$_}{whatever}==$something_else;

foreach (@{$row_data{fields}}){ push @{$new_row_data{fields}}, $_ if $
+{$_}{whatever}==$something_else;

#This bit doesn't at all
$row_data{groups}=$new_row_data{groups};
$row_data{fields}=$new_row_data{fields};

[download]

There are other hash keys in row_data that I wish to keep. I could just copy them over to %new_row_data one by one, but in the spirit of knowing what's going on, could someone show me the correct way to do it. I wanted to use map originally, but I couldn't quite get that going right either.

____________________
Jeremy
I didn't believe in evil until I dated it.

In reply to Wrestling with HoL by jepri

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