Thanks Rolf. This answered what I was trying to do achieve with map. I was hoping to be able to declare and initiate %hash in one line but couldn't get it to work because of the collision and couldn't be sure if it was possible. 
 You can't have map returning nested hashes assigned to a top-level ha
+sh, otherwise entries from different lines would collide (2 x Sidney,
+ 2 x Canberra)

 my %hash = map { entry1 => { entry2 => 1} } <> # collisions of entry1

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In reply to Re^2: Possible for Map to create Hash of Hash? by konnjuta
in thread Possible for Map to create Hash of Hash? by konnjuta

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