sorry if it's been discussed as i don't know what the search keyword
for this scenario. it actually came up from _mistype_ (notice the
comma).

m:~ arie$ irb
>> h = {}
=> {}
>> h[:a] = 1,
?> h[:b] = 2
=> [1, 2]
>> h
=> {:a=>[1, 2], :b=>2}


-- 
r9 = { name: Rie!, ym: riyari3, skype: rubyninja,
blog: http://tinyurl.com/2bjgvn,
ruby: http://www.ruby-lang.org/id/about/ }