logging

Simplified logging in IO for application writers.

logging is a wrapper around fast-logger which makes it easy to log from IO. It provides the following conveniences on top of those libraries:

• A set of shorter functions to type: debug, log, warn, plus others that flush after each message, or which allow providing a message source string.

• Logging variants of error, trace and traceShow, called errorL, traceL and traceShowL. These use unsafePerformIO in order to act as direct replacements, so the usual caveats apply.

• A global function, setDebugLevel, which uses a global IORef to record the logging level, saving you from having to carry around the notion of "verbosity level" in a Reader environment.

• A set of "timed" variants, timedLog and timedDebug, which report how long the specified action took to execute in wall-clock time.