Jetbrains Rider does this does for C# code (I think Visual Studio does as well). Its inlay hints feature will also show you hints with the result type of each

Jetbrains Rider does this does for C# code (I think Visual Studio does as well). Its inlay hints feature will also show you hints with the result type of each line as the data is transformed. I haven't explicitly tested but I would imagine their IDEs for other languages behave the same.