Example: The (informally
specified) semantics of commands in Mini-Triangle.
Commands are executed to
update variables and/or to perform input/output.
The assignment command V := E is executed as follows:
first the expression E is evaluated to yield a
value x
then x is assigned to
the variable named V
The sequential command C1;C2 is executed as follows:
first the command C1 is executed
then the command C2 is executed
etc.