Perhaps you are looking for something like this instead?
use strict;
use warnings;

my $data = do {local $/; <DATA>};

$data =~ y/ \n/ /s;

# add the following if you want to strip space after >
# and before < characters.
# $data =~ s/(?<=>)\s|\s(?=<)//gm;

print "$data\n";

__DATA__
<thing>
 condition
   condition
    randomness
      other junk
        more junk

</thing>

[download]
and the output -
<thing> condition condition randomness other junk more junk </thing>

[download]

In reply to Re: multi line matching problem by Roger
in thread multi line matching problem by jcpunk

Title:
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