4 ms·

but, Expression can be created from string, doesn't it?

• mythz 7y ago
  Parsed by who, the C# compiler? I'm not aware of anything that generates C#'s Expression AST from a string, other than a C# Compiler. You can use Roslyn in code, but that's using the C# compiler in process.
  • gpderetta 7y ago
    The code->AST is done of course at compile time (there is no reason to delay), but I believe the expression tree itself is processed by linq at runtime. You can build expressions programmatically at runtime as well (and then ask the runtime to optmize them to bytecode). I remember doing it years ago, it was surprisingly simple (and very powerful).
    • mythz 7y ago
      Of course the Expression's AST generated by the C# compiler is analyzed at runtime, how else could it be done?