fishy commented on PR #3812:
URL: https://github.com/apache/thrift/pull/3812#issuecomment-5587904435

   The discussion of whether to use type alias in go had came up before and 
rejected. The reason we don't want it is it will lose some compile time 
enforcement.
   
   For example, someone can have this typedef in thrift:
   ```thrift
   typedef i64 TimestampMilliseconds
   ```
   
   With the current not-type-alias implementation, we the generated go code is:
   ```
   type TimestampMilliseconds int64
   ```
   
   It's convertible with int64 but _not the same type_. so when using it, you 
mostly are required to use an explicit typecasting like this
   
   ```go
   obj.StartTime := package.TimestampMilliseconds(t.UnixMilli())
   ```
   
   while this won't compilre:
   
   ```go
   obj.StartTime := t.UnixMilli()
   ```
   
   as `t.UnixMilli()` gives you `int64` not `TimestampMilliseconds`.
   
   now imagine if someone has a bug and used 
[`UnixNano`](https://pkg.go.dev/time#Time.UnixNano) instead. With forced 
explicit casting, it's very obvious at a glance that there is a bug:
   
   ```go
   obj.StartTime := package.TimestampMilliseconds(t.UnixNano())
   ```
   
   You lost that when using type alias.


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