A Compositional Semantics of Assignment — or, L-values Demystified and Deprecated
In Fortran/Algol tradition, a mutable variable is a variable that can be directly mutated as such by assignment, increment, etc. In contrast, ML tradition uses variables of reference types, bound to ‘boxed values’, or reference cells. These are ordinary, lambda-calculus variables that can be substituted for but not mutated…
