foreach $key(keys %tagcorpus){
    print "\n$key";
    return($key);
}

##</code><code>##

undef %h; 
@h{'a'..'m'}=1..13;

print each %h, ' - ' for 1..7; 
# Gives "e 5  - a 1  - m 13  - d 4  - j 10  - l 12  - c 3  -"
# The first seven key/value pairs in some order

print each %h, ' - ' for 1..7; 
# Gives "k 11  - h 8  - b 2  - g 7  - f 6  - i 9  -  -"  
# The last 6 + an empty pair to indicate the end of the list


undef %h; @h{'a'..'m'}=1..13
print each %h, ' - ' for 1..7;
# Gives "e 5  - a 1  - m 13  - d 4  - j 10  - l 12  - c 3  -" The first seven as before

 @h{'n'..'z'} = 14..26; # Now modify the hash by adding some new stuff

# Now continue iterating them from whre we were before
print each %h, ' - ' for 1..7; 
# Gives "p 16  - k 11  - h 8  - g 7  - f 6  - t 20  - i 9  -" 
# Looks good, no empty pair so it knows there are more
# and nothing is duplicated...

print each %h, ' - ' for 1..7; # Print the next batch
# "e 5  - n 14  - v 22  - m 13  - s 19  - l 12  - c 3  -"  Whoops!!
# Even though we haven't had the empty pair to indicate the of the list
# Were starting to see some elements being repeated.
# We've already seen e, m, j, l & c in the first batch. 

print each %h, ' - ' for 1..7;
# Gives "p 16  - b 2  - q 17  - z 26  - o 15  -  - w 23  -" NOTE the empty pair!
# Now we have reached the end of the list, wrapped and are starting again
# But the first one we get this time is 'w' rather than 'e' that we got first time
# And it isn't 'a' in either case.