Go中应该避免使用反射吗？

Question

I'm new to Go and also new to the concept of reflection, but should and can the usage of reflect package be avoided in Go? Is there a scenario where reflect is unavoidable?

Answer 1

There are a few problem domains where reflection makes it easier to write reusable libraries:

• marshalling/unmarshalling, plenty of examples in the standard library, e.g. encoding/json, encoding/xml
• formatting, e.g. text/template, html/template, fmt.Printf.

However there is a price you pay for using reflection:

• compile time errors become runtime errors (e.g. fmt.Printf("%d", stringVariable))
• performance becomes worse

Very often an alternative solution exists that do not require reflection such as code generation, that is used by marshalling libraries like protobuf or thrift.

I agree with @volker that you should use reflection only when you know that it will simplify already existing code and aware of all downsides.