rudlorenz · rudlorenz · Feb 24, 2021 · Feb 15, 2021 · Feb 15, 2021 · Feb 18, 2021
diff --git a/Expressions/main.cpp b/Expressions/main.cpp
@@ -1,20 +1,19 @@
 #include "Parser.h"
 
 #include "fmt/core.h"
-#include "fmt/format.h"
 
 int main()
 {
     std::string input = "-x*x/y";
     auto result = parser::parse(input);
-    if (result == nullptr) {
+    if (!result) {
         fmt::print(stderr, "Something wrong!");
         return 0;
     }
 
     fmt::print(stdout, "input : {}\n", input);
     fmt::print(stdout, "as expressions : {}\n", result->to_expr_string());
-    fmt::print(stdout, "d/dx : {}\n", result->diff("x")->to_string());
+    fmt::print(stdout, "d/dx : {}\n", result->diff("x").to_string());
 
     return 0;
 }
diff --git a/Expressions/src/BinaryExpression.h b/Expressions/src/BinaryExpression.h
diff --git a/Expressions/src/CMakeLists.txt b/Expressions/src/CMakeLists.txt
@@ -21,10 +21,9 @@ FetchContent_MakeAvailable(fmtlib)
 target_sources(
         expressions
         PRIVATE
-            Stack.h Number.h Variable.h BinaryExpression.h Sum.h Sub.h
-            Mul.h Div.h SinCos.h Negate.h
+            Stack.h Expression.cpp
         PUBLIC
-            Expression.h Parser.h Expressions.h ParserInternal.h ParserInternal.cpp Parser.cpp
+            Expression.h Parser.h ParserInternal.h ParserInternal.cpp Parser.cpp
 )
 
 target_include_directories(

diff --git a/Expressions/src/Div.h b/Expressions/src/Div.h