intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 30 insertions, 0 deletions

diff --git a/library/cpp/lwtrace/example5/lwtrace_example5.cpp b/library/cpp/lwtrace/example5/lwtrace_example5.cpp
new file mode 100644
index 0000000000..1c324473c2
--- /dev/null
+++ b/library/cpp/lwtrace/example5/lwtrace_example5.cpp
@@ -0,0 +1,30 @@
+#include <library/cpp/lwtrace/all.h>
+#include <library/cpp/lwtrace/lwprobe.h>
+
+template <ui64 N>
+ui64 Fact() {
+    ui64 result = N * Fact<N - 1>();
+
+#ifndef LWTRACE_DISABLE
+    // Note that probe is create on the first pass
+    // LWTRACE_DECLARE_PROVIDER and LWTRACE_DEFINE_PROVIDER are not needed
+    // (Provider is created implicitly)
+    static NLWTrace::TLWProbe<ui64> factProbe(
+        "LWTRACE_EXAMPLE_PROVIDER", "FactProbe_" + ToString(N), {}, {"result"});
+
+    LWPROBE_OBJ(factProbe, result);
+#endif // LWTRACE_DISABLE
+    return result;
+}
+
+template <>
+ui64 Fact<0>() {
+    return 1;
+}
+
+int main() {
+    Fact<6>();                       // First run is required to create probes we can use later in trace query
+    NLWTrace::StartLwtraceFromEnv(); // parse trace query and create trace session
+    Cout << Fact<6>() << Endl;       // actually trigger probes
+    return 0;
+}