What compile flags are you using? If you look at the source of the net module, all of the ssl types are defined inside a compile time if statement. The `when defineSsl` block: [https://github.com/nim-lang/Nim/blob/master/lib/pure/net.nim#L82](https://github.com/nim-lang/Nim/blob/master/lib/pure/net.nim#L82)
If you do not compile your program with the `-d:ssl` flag, those types don't ever get compiled, so you can't catch them. You must remember to use the `-d:ssl` flag when compiling or If you want your code to work both with and without ssl support, you also must use `when defineSsl:`.
