generated at
monadic region

ここでみた
https://okmij.org/ftp/Haskell/regions.html
http://www.cs.cornell.edu/people/fluet/research/rgn-monad/
https://wiki.haskell.org/Monadic_regions
https://dl.acm.org/doi/10.1145/1016848.1016867
chrome-extension://oemmndcbldboiebfnladdacbdfmadadm/https://www.cs.cornell.edu/people/fluet/research/rgn-monad/JFP06/jfp06.pdf
https://okmij.org/ftp/Haskell/types.html#monadic-regions
Lightweight monadic regions
https://dl.acm.org/doi/10.1145/1543134.1411288
Oleg Kiselyov
https://okmij.org/ftp/Haskell/regions.html#light-weight