Method to supress multiple warnings

General Usage
4

Hi, I just did a little code dive. Usually, the counter is only reset when you start a new session, but you can either replace the logger or reset the counter manually:

julia> function logtest()
           x = rand()*rand()
           @warn "Some message" maxlog=3
           return x
       end;

julia> function runlogtest(n)
           for _ in 1:n
               logtest()
           end
       end;

julia> runlogtest(10)
┌ Warning: Some message
└ @ Main REPL[14]:3
┌ Warning: Some message
└ @ Main REPL[14]:3
┌ Warning: Some message
└ @ Main REPL[14]:3

julia> runlogtest(10) # this does not log again

julia>

Here’s how to do it. I choose to reset the message_limits counter instead of replacing the entire logger. The key is, that every log message gets an id internally, which is relatively stable and is for example used to check against the maxlog limit. The id can easily be set by hand and the corresponding counter reset:

julia> using Logging

julia> function logtest_resettable()
           a = rand()
           @warn "This warning will be shown twice per run!" a=a maxlog=2 _id=:ResetMyCounter # write whatever you want here, but it should be a symbol
           return a
       end
logtest_resettable (generic function with 1 method)

julia> function runtest_and_reset(n)
           for _ in 1:n
               logtest_resettable()
           end
           Logging.current_logger().message_limits[:ResetMyCounter] = 2 # insert appropriate id here and maxlog number
       end
runtest_and_reset (generic function with 1 method)

julia> runtest_and_reset(5)
┌ Warning: This warning will be shown twice per run!
│   a = 0.33945681655296056
└ @ Main REPL[21]:3
┌ Warning: This warning will be shown twice per run!
│   a = 0.835372097983738
└ @ Main REPL[21]:3
2

julia> runtest_and_reset(5)
┌ Warning: This warning will be shown twice per run!
│   a = 0.2205420236924749
└ @ Main REPL[21]:3
┌ Warning: This warning will be shown twice per run!
│   a = 0.5396194992303944
└ @ Main REPL[21]:3
2

And it indeed does log twice per run. I kinda believe there should be a package for that already, but as long as we don’t find it, this should do :slight_smile: Have a nice day.

Edit: on second though, Logging. with_logger(myfunction, Logging.ConsoleLogger()) is probably easier and more stable. I’d advise on using that one

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