Conditional can take a lambda

badaix · Feb 24, 2021 · fd4a341 · fd4a341
1 parent 77e8690
commit fd4a341
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Showing 2 changed files with 22 additions and 4 deletions.
diff --git a/aixlog_example.cpp b/aixlog_example.cpp
@@ -132,4 +132,16 @@ int main(int /*argc*/, char** /*argv*/)
     LOG(INFO) << every_x << "4th will not be logged\n";
     LOG(INFO) << every_x << "5th will not be logged\n";
     LOG(INFO) << every_x << "6th will be logged\n";
+
+    AixLog::Conditional not_every_3(AixLog::Conditional::EvalFunc([] {
+        static size_t n(0);
+        return (++n % 3 != 0);
+    }));
+
+    LOG(INFO) << not_every_3 << "1st will be logged\n";
+    LOG(INFO) << not_every_3 << "2nd will be logged\n";
+    LOG(INFO) << not_every_3 << "3rd will not be logged\n";
+    LOG(INFO) << not_every_3 << "4th will be logged\n";
+    LOG(INFO) << not_every_3 << "5th will be logged\n";
+    LOG(INFO) << not_every_3 << "6th will not be logged\n";
 }
diff --git a/include/aixlog.hpp b/include/aixlog.hpp
@@ -269,23 +269,29 @@ struct TextColor
  */
 struct Conditional
 {
-    Conditional() : Conditional(true)
+    using EvalFunc = std::function<bool()>;
+
+    Conditional() : func_([](void) { return true; })
+    {
+    }
+
+    Conditional(const EvalFunc& func) : func_(func)
     {
     }
 
-    Conditional(bool value) : is_true_(value)
+    Conditional(bool value) : func_([value](void) { return value; })
     {
     }
 
     virtual ~Conditional() = default;
 
     virtual bool is_true() const
     {
-        return is_true_;
+        return func_();
     }
 
 protected:
-    bool is_true_;
+    EvalFunc func_;
 };
 
 /**