[tubthumper8]

"Ignoring" is the charitable framing of this.

Sum types and product types are fundamental to a type system, the same way that addition and multiplication are fundamental to arithmetic.

You wouldn't design a language with only multiplication and not addition. You wouldn't design boolean operations with only `&&` and not `||`. You wouldn't design bitwise operations with only `&` and not `^`. You wouldn't design set operations with only `∩` and not `∪`.

The alternative to "ignore" here is "ignorant", so it seems a nicer intention that they were aware of the fundamentals and chose not to use them.

[mappu]

Thanks for your input! All the design proposal RFCs have shown they cause an issue with the Go Compatibility Promise whereby adding any enum value can cause a semver-MAJOR breaking change. This causes a greater rate of ecosystem churn which, in every design proposal so far, has been deemed a net negative outweighing the modelling benefits.

[tubthumper8]

Yep, I'm aware. The question you asked was about the Go language designers ignoring the fundamentals, which is the root cause of this situation today where fundamentals can't be bolted on to the language later