I would like not to start a flame here but the difference is mainly in the meaning. 

While the **"token index"** means **"the index of the token"** which implies that **"the token has some index"**  which is misleading as the token has no index. The particular token information **DO** have an index in the token representing array. 

I think the difference is clear. Why do you insist on less accurate description?

As these constants are a part of the [**README**](https://github.com/nette/tokenizer/blob/master/readme.md) I disagree that noone should care about them.