Interaction with ML
ML, like Lisp, provides a READ-EVAL-PRINT loop.
Whenever ML prints the value of an expression, it also prints the TYPE of the value.
ML keeps track of the types of variables and functions by solving systems of constraints.
ML does not use assignment. On the other hand, it does use binding. Thus it uses the ‘=‘ sign in a mathematical sense.
val flavor = "strawberry" ;
binds a string to an identifier.