Are there versions of map and grep that operate on hashes, rather than arrays? I'm looking for terse, well behaved, faithful cousins of array map and grep (or perhaps techniques using normal map and grep, but these seem un-terse).
These would iterate over the (k,v) pairs in the hash, providing them in v = $_, k = something, and produce a new hash.
hmap would only change the value (key is the same, it's part of the identity of the pair), but could be used in the BLOCK. hgrep includes (k,v) if expr is true.
I can come up with an implementation, but is there a really good one already done? Really good = on level of normal map and grep.