
Overview of Processing of Some Languages 345
variable and leaves it on the stack. Therefore, the behaviour of show-state is to print a number that
represents the current value of state.
When you execute word1, it prints the number 0, indicating that the system is interpreting. When
the text interpreter compiled the definition of word1, it encountered show-state whose compilation
semantics are to append its interpretation semantics to the current definition. When you execute
word1, it performs the interpretation semantics of show-state.
At the time that word1, and therefore show-state, are executed, the system is interpreting.
When you press ...