Honorable monks!

(EDIT: for a simplified bug-demo see update further down and one-liner post)

For Re: Syntax explanation required I tried to show the elimination of duplicates when assigning a list of two hashes to a third hash.

But while the third hash holds the correct results (line 105) the return value (line 102) of the assignment looks very weird, and I can't really explain whats happening.

  DB<100> %h1=(a=>1,b=>2);
 => ("a", 1, "b", 2)
 
  DB<101> %h2=(a=>11,c=>3);
 => ("a", 11, "c", 3)
 
  DB<102> %h=(%h1,%h2)
 => ("b", 2, "b", 2, "c", 3)
 
  DB<103> @ret = ( %h=(%h1,%h2) )
 => ("b", 2, "b", 2, "c", 3)
 
  DB<104> \@ret
 => ["b", 2, "b", 2, "c", 3]
 
  DB<105> %h
 => ("c", 3, "a", 11, "b", 2)

[download]

to be sure that it's not just my repl showing buggy results I reproduced it again on the console:

> perl
%h1=(a=>1,b=>2);
%h2=(a=>11,c=>3);
print (%h3=(%h1,%h2),"\n");
 
print %h3;
 
__END__
b2b2c3
c3a11b2

[download]

I'm still suffering from a little hangover from recent tumultuous events ... ;-)

So please could someone tell me what I am missing here?

Cheers Rolf

UPDATE:

I was able to further isolate whats happening to a simple list assignment:

  DB<107> %h=("a", 1, "b", 2, "c", 3, "a", 11)
 => ("b", 2, "b", 2, "c", 3)
 
  DB<108> %h=("a", 1, "b", 2, "c", 3, "d", 4)
 => ("a", 1, "b", 2, "c", 3, "d", 4)
 
  DB<110> %h=("a", 1, "a", 11, "b", 2)
 => ("a", 11, "a", 11)

[download]

seems like that the fact that duplicated keys are eliminated (here a) somehow confuses the returned value.

In reply to return of hash-assigment in list context (bug?) by LanX

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