Simple native Kernel#callsite for Ruby MRI (c) 2009, 2010 Lourens Naudé (methodmissing) http://github.com/methodmissing/callsite This library works with Ruby 1.8. Examples : callsite() #=> -612079380 callsite() #=> -612079378 callsite() #=> -612079376 callsite(5) #=> -1165103632 # only hash against the last 5 stack frames callsite(20) #=> 0 # less than 20 stack frames To run the test suite: rake To run the benchmarks: rake bench Todo : Account for the last function arguments ( ala super )