jq is useful to slice, filter, map and transform structured json data.
brew install jq
Latency Comparison Numbers (~2012) | |
---------------------------------- | |
L1 cache reference 0.5 ns | |
Branch mispredict 5 ns | |
L2 cache reference 7 ns 14x L1 cache | |
Mutex lock/unlock 25 ns | |
Main memory reference 100 ns 20x L2 cache, 200x L1 cache | |
Compress 1K bytes with Zippy 3,000 ns 3 us | |
Send 1K bytes over 1 Gbps network 10,000 ns 10 us | |
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD |
:set prompt "> " | |
:set -isrc | |
:load Main |
----------------------------- | |
-- Domain.hs | |
type SessionId = Text | |
type UserId = Text | |
type User = Text | |
class (Monad m) => UserRepo m where | |
getUserById :: UserId -> m User |