Formal review of std.lexer

[Meta]

On Monday, 24 February 2014 at 22:14:34 UTC, Dejan Lekic wrote:
> No criticism should stop this module being accepted, as we do 
> not have any other lexer in the runtime anyway. Therefore I 
> suggest we accept std.lexer until a better solution comes up. 
> Naturally anyone should be encouraged to provide a better 
> solution by submitting a pull request to Phobos developers...

The problem is that this is what has been done before, and now we 
are more or less stuck with outdated, sometimes poorly-written, 
often buggy modules (std.signals being one example).