class ActiveSupport::Logger::SimpleFormatter

def call(severity, timestamp, progname, msg)

Experimental RBS support (using type sampling data from the type_fusion project). 

def call: (String severity, Time timestamp, nil progname, String msg) -> String

This signature was generated using 336 samples from 3 applications.

This method is invoked when a log event occurs 
def call(severity, timestamp, progname, msg)
  "#{String === msg ? msg : msg.inspect}\n"
end