performs a simple check of consistency of the inverse with the forward
map by a check if every value-key pair corresponds to a key-value pair
with identical references and vice versa.
Instance-based samplers with diverse sampling methods, including beta, gamma,
multinomial, and Dirichlet distributions as well as Dirichlet processes,
using Sethurahman's stick-breaking construction and Chinese restaurant
process.
copies the pattern string content with an new matcher set to the region
of the current one but the matchresult my set, ie., all references to
groups information of the last match are kept.