Haskell/Debugging
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< Haskell
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[edit] Incremential development with GHCi
[edit] Debugging with Hat
[edit] Tracing with Debug.Trace
import Debug.Trace
trace has a type signature of trace :: String -> a -> a It is designed this way to be able to easily insert it in code.
before:
main = (1 + 2)
after:
main = trace "adding" (1 + 2)
You find a helper that uses show useful
debug :: Show a => a -> a
debug x = trace (show x) x