warn.rb
Heads up: This description was created by AI and might not be 100% accurate.
This Ruby code snippet demonstrates basic usage of the Logger
class. It initializes a logger that outputs to standard output (STDOUT) and then sets the logging level to WARN
. Messages with severity levels of WARN
and higher (e.g., ERROR
, FATAL
) will be printed, while INFO
and DEBUG
messages are suppressed because the logging level is set to WARN
. The output shows only the WARN
message being printed to the console, along with a timestamp and severity level.
Additional Note
Ref. https://docs.ruby-lang.org/ja/latest/library/logger.html
Ruby code snippet
require 'logger'
#=> true
logger = Logger.new(STDOUT)
#=>
#<Logger:0x00007ffafdfa1e28
puts "Level WARN"
Level WARN
#=> nil
logger.level = Logger::WARN # <= change level
#=> 2
logger.warn("Nothing to do!") # output
W, [2025-10-11T11:55:27.814483 #2932] WARN -- : Nothing to do!
#=> true
logger.info("Program started") # none
#=> true
logger.debug("Created logger") # none
#=> true
Executed with Ruby 3.4.7
.