Reflection and meta programming (Go Time #133)

Mat, Jon, and Jaana discuss reflection and meta programming. How do other languages use reflection, and how does that differ from Go’s approach? What libraries are using reflection well? What are some examples of bad times to use reflect? What alternative approaches exist? And what are those weird struct tags I keep seeing in Go code?

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Featuring:

• Mat Ryer – GitHub, LinkedIn, Bluesky, X
• Jon Calhoun – Website, GitHub, X
• Jaana Dogan – Website, GitHub, X

Show Notes:

• Laws of Reflection - From the Go blog
• Oto - Library by Mat using AST to generate code
• form - Jon’s form library that uses reflect
• form’s without reflect - An example from Jon of creating forms without reflect
• Language Server Protocol - Created by Microsoft to make it easier to create autocompletion for different editors
• A new Go API for Protocol Buffers - A writeup of changes in protobuf to allow for a type of reflection

Something missing or broken? PRs welcome!