To do:
user guide
- introduction: goals, philosophy
- structure of a program
- variables, data, logic, flow
- the io model: how and when to sync
- the object model: constructors, prototypes, interfaces
- strings: sequences of unicode chars
- sequences and parallelism, how to get the most out of radian

technical reference
- grammar
- dataflow-oriented semantic model
- semantics of object model
- api of intrinsic objects (literals, generators, tasks, modules)
- api of each built in library