얼랑의 dbg
모듈이 유용한 기능을 제공 : 추적 여기
내 두 가지 기능이 있습니다.
이
설치 프로그램 : 당신이 모듈에있는 함수를 호출 할 때마다 지금
1> c(a). % load a.erl
{ok,a}
2> dbg:tracer(). % start the default trace message receiver
{ok,<0.71.0>}
3> dbg:p(all, c). % setup call tracing on all processes
{ok,[{matched,[email protected],34}]}
4> dbg:tpl(a, '_', '_', []). % trace all functions in a
{ok,[{matched,[email protected],5}]}
, 이름과 인수가 쉘에 인쇄됩니다 다음은 코드를 모듈 a
에 가정이 함수를 추적 할 것입니다 방법 .
5> a:sum(lists:seq(1, 10)).
(<0.64.0>) call a:sum([1,2,3,4,5,6,7,8,9,10])
(<0.64.0>) call a:sum([2,3,4,5,6,7,8,9,10])
(<0.64.0>) call a:sum([3,4,5,6,7,8,9,10])
(<0.64.0>) call a:sum([4,5,6,7,8,9,10])
(<0.64.0>) call a:sum([5,6,7,8,9,10])
(<0.64.0>) call a:sum([6,7,8,9,10])
(<0.64.0>) call a:sum([7,8,9,10])
(<0.64.0>) call a:sum("\b\t\n")
(<0.64.0>) call a:sum("\t\n")
(<0.64.0>) call a:sum("\n")
(<0.64.0>) call a:sum([])
55
6> a:tail_sum(lists:seq(1, 10)).
(<0.64.0>) call a:tail_sum([1,2,3,4,5,6,7,8,9,10])
(<0.64.0>) call a:tail_sum([1,2,3,4,5,6,7,8,9,10],0)
(<0.64.0>) call a:tail_sum([2,3,4,5,6,7,8,9,10],1)
(<0.64.0>) call a:tail_sum([3,4,5,6,7,8,9,10],3)
(<0.64.0>) call a:tail_sum([4,5,6,7,8,9,10],6)
(<0.64.0>) call a:tail_sum([5,6,7,8,9,10],10)
(<0.64.0>) call a:tail_sum([6,7,8,9,10],15)
(<0.64.0>) call a:tail_sum([7,8,9,10],21)
(<0.64.0>) call a:tail_sum("\b\t\n",28)
(<0.64.0>) call a:tail_sum("\t\n",36)
(<0.64.0>) call a:tail_sum("\n",45)
(<0.64.0>) call a:tail_sum([],55)
55
또한 return_trace()
을 반환 일치 스펙을 사용하여 반환 된 값을 기록하기 위해 추적을 요청할 수 있습니다. 완벽하게 작동
7> dbg:tpl(a, '_', '_', [{'_',[],[{return_trace}]}]).
(<0.64.0>) call a:module_info()
{ok,[{matched,[email protected],5},{saved,1}]}
8> a:sum(lists:seq(1, 10)).
(<0.64.0>) call a:sum([1,2,3,4,5,6,7,8,9,10])
(<0.64.0>) call a:sum([2,3,4,5,6,7,8,9,10])
(<0.64.0>) call a:sum([3,4,5,6,7,8,9,10])
(<0.64.0>) call a:sum([4,5,6,7,8,9,10])
(<0.64.0>) call a:sum([5,6,7,8,9,10])
(<0.64.0>) call a:sum([6,7,8,9,10])
(<0.64.0>) call a:sum([7,8,9,10])
(<0.64.0>) call a:sum("\b\t\n")
(<0.64.0>) call a:sum("\t\n")
(<0.64.0>) call a:sum("\n")
(<0.64.0>) call a:sum([])
(<0.64.0>) returned from a:sum/1 -> 0
(<0.64.0>) returned from a:sum/1 -> 10
(<0.64.0>) returned from a:sum/1 -> 19
(<0.64.0>) returned from a:sum/1 -> 27
(<0.64.0>) returned from a:sum/1 -> 34
(<0.64.0>) returned from a:sum/1 -> 40
(<0.64.0>) returned from a:sum/1 -> 45
(<0.64.0>) returned from a:sum/1 -> 49
(<0.64.0>) returned from a:sum/1 -> 52
(<0.64.0>) returned from a:sum/1 -> 54
(<0.64.0>) returned from a:sum/1 -> 55
55
9> a:tail_sum(lists:seq(1, 10)).
(<0.64.0>) call a:tail_sum([1,2,3,4,5,6,7,8,9,10])
(<0.64.0>) call a:tail_sum([1,2,3,4,5,6,7,8,9,10],0)
(<0.64.0>) call a:tail_sum([2,3,4,5,6,7,8,9,10],1)
(<0.64.0>) call a:tail_sum([3,4,5,6,7,8,9,10],3)
(<0.64.0>) call a:tail_sum([4,5,6,7,8,9,10],6)
(<0.64.0>) call a:tail_sum([5,6,7,8,9,10],10)
(<0.64.0>) call a:tail_sum([6,7,8,9,10],15)
(<0.64.0>) call a:tail_sum([7,8,9,10],21)
(<0.64.0>) call a:tail_sum("\b\t\n",28)
(<0.64.0>) call a:tail_sum("\t\n",36)
(<0.64.0>) call a:tail_sum("\n",45)
(<0.64.0>) call a:tail_sum([],55)
(<0.64.0>) returned from a:tail_sum/2 -> 55
(<0.64.0>) returned from a:tail_sum/2 -> 55
(<0.64.0>) returned from a:tail_sum/2 -> 55
(<0.64.0>) returned from a:tail_sum/2 -> 55
(<0.64.0>) returned from a:tail_sum/2 -> 55
(<0.64.0>) returned from a:tail_sum/2 -> 55
(<0.64.0>) returned from a:tail_sum/2 -> 55
(<0.64.0>) returned from a:tail_sum/2 -> 55
(<0.64.0>) returned from a:tail_sum/2 -> 55
(<0.64.0>) returned from a:tail_sum/2 -> 55
(<0.64.0>) returned from a:tail_sum/2 -> 55
(<0.64.0>) returned from a:tail_sum/1 -> 55
55
:
sum
점진적으로tail_sum
달리 값을 빌드하는 방법이 명확하게 보여줍니다! 감사합니다. –방금 return_trace를 포함하도록 답을 편집했습니다. 이것은 당신에게 더 유용 할 것입니다. 추적은 Erlang VM의 가장 좋아하는 기능 중 하나입니다! – Dogbert