4 ms·

https://cs.opensource.google/go/go/+/refs/tags/go1.21.6:src/errors/wrap.go;l=17 https://cs.opensource.google/go/go/+/refs/tags/go1.21.6:src/...

• Thaxll 3y ago
  But this is a detail of implementation, user code does not use reflection with errors.
  • sidlls 3y ago
    That "detail of implementation" is what is used by user code, e.g., `myError.As(...)` uses reflection, implicitly.
    • Thaxll 3y ago
      Then what? It has 0 performance impact, we're talking about error handling here, it's rare and not in hot path.
      • sidlls 3y ago
        It does not have 0 performance impact, it's not rare, and in applications that are in the hot path, error handling is also in the hot path.
        • Thaxll 3y ago
          No, it only executes when you enter the err != nil block so it's almost never called, again 0 impact on performance.
• derekperkins 3y ago
  I wouldn't classify type assertion as reflection. It's a super fast type check of the object header, not dynamic reflection.