The second answer may be incorrect. According to the question: we are to find all the matches between the keys in %a and %b, and if there is a match, assign the value of the matching element from %b into the corresponding element in %a.

A hash slice won't work in this case, consider:

my %a = (
  a => 1,
  b => 2,
  c => 3,
);

my %b = (
  b => 4,
  d => 8,
  f => 12,
);

@a{ keys %b } = values %b;

[download]

Now, %a is:

%a = (
  a => 1,
  b => 4,
  c => 3,  
  d => 8,
  f => 12,
);

[download]

Which is the incorrect answer, according to the question. If we use a hash slice, we'll be copying all the elements from %b into %a, regardless if there are any matches, or not.

In reply to (dkubb) Re: (2) Answer: How do I make all the values in %a with common keys in %b equal to %b's keys? by dkubb
in thread How do I make all the values in %a with common keys in %b equal to %b's values? by draco_iii

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