Classes with reference semantics (R6)
The R6 package allows the creation of classes with reference semantics, similar to R’s built-in reference classes. Compared to reference classes, R6 classes are simpler and lighter-weight, and they are not built on S4 classes so they do not require the methods package. These classes allow public and private members, and they support inheritance, even when the classes are defined in different packages.

A Simple General Purpose N-Gram Tokenizer (ngramrr)
A simple n-gram (contiguous sequences of n items from a given sequence of text) tokenizer to be used with the ‘tm’ package with no ‘rJava’/’RWeka’ dependency.

Piecewise Exponential Model for Time to Progression and Time from Progression to Death (pssm)
Estimates parameters of a piecewise exponential model for time to progression and time from progression to death with interval censoring of the time to progression and covariates for each distribution using proportional hazards.