my $items = join('', multimap( 2, { $_[0] . '=' . $_[1] . "\n" } %ENV));

Maybe a little prettier, though.

Like this?

sub multimap (&$@) {
  my $fn = shift;
  my $n = shift;
  my @res;
  while (@_) {
    push @res, $fn->(splice (@_, 0, $n));
  }
  @res;
}

print multimap { "$_[0]=$_[1]\n" } 2, %ENV;
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I tried to reverse the order of the first two arguments, but then the prototypes misbehaved. Reminded me of why I usually don't try to use them.

I spend very little of my time displaying native Perl data types. When I do need to do it, I usually want to do it with Data::Dumper. When I don't want to do it that way, I generally have some target output format which is generally not going to fit your simple display above. Which I could write already as:

join "\n", map "$_=$ENV{$_}", sort keys %ENV;
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Plus the fact that this join interface bears no relationship to the usual join strikes me as a design decision that can do nothing but lead to grief later.

sub hash_join {
    my ($hash_ref, $sep1, $sep2) = @_;
    my $string = "";
    $string .= "${_}${sep}$hash_ref->{$_}${sep2}"
        for sort keys %$hash_ref;
    $string;
}

my $string = hash_join \%ENV, " = ", "\n";
print $string;
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works just as well, as well as having the benefit of being very obvious as to what you're doing. Your join would have to have too many new arguments, I think. But, that's just my opinion on the matter.

I'd do:

sub hash_join (\%$$) {
  my ($h, $between, $end) = @_;
  my $str;

  while (my($k,$v) = each %$h) {
    $str .= "$k$between$v$end";
  }

  return $str;
}

print hash_join %ENV, "=", "\n";
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japhy -- Perl and Regex Hacker

%hash = (%hash, @more);

%hash = (%hash, %more);

@hash{@keys} = @values;
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   MeowChow                                   
               s aamecha.s a..a\u$&owag.print

How are any of these creating a string representation of hash contents?

I read your node as using join to append a list to hash. Now that I look at the names you chose for your hash keys, I can see what you meant more clearly; though I hadn't bothered to consider the names because I don't forsee any Perl built-ins using named parameters.

   MeowChow                                   
               s aamecha.s a..a\u$&owag.print

use English;

local $KEYVAL_SEP = '=';
local $INTERPAIR_SEP = "\n";

my $join = "%hash";
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