I fixed up your post, added some formatting to show how that is done nowadays (if you click edit on it then you can see what the source looks like, or if you click the history icon in the upper-right of the post then you can see the precise changes I did). 
If you enclose inline ‘code’ like List<WorldgenObject> like `List<WorldgenObject>` then it will appear like List<WorldgenObject>.
Also as you seemed to have noticed (since spaces were added to prevent it) something like "List<WorldgenObject>" will appear like “List” in the post, but if you type "List\<WorldgenObject\>" so you ‘escape’ the greater-than/less-than signs then they will post directly, otherwise it’s trying to infer it as an HTML tag, however you don’t need to do that when surrounding it with `'s like `List<WorldgenObject>` just becomes List<WorldgenObject>.
In other words, always put inline code snippets inside of `'s to prevent from from doing weird things. And as for multi-line code you use code fences, like:
```
dim {
B:Titan_true=true
}
```
And this will appear like:
dim {
B:Titan_true=true
}
It defaults to Java-style syntax coloring, you can change that to something else by specifying it after the first ``` set like this:
```toml
dim {
B:Titan_true=true
}
```
So this would format it like the toml config language (which this example isn’t, but it’s also just an example). ^.^