You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
11 lines
611 B
11 lines
611 B
2 years ago
|
|
||
|
|
Exercise 4.17: Draw diagrams of the environment
|
||
|
|
in effect when evaluating the expression ⟨e3⟩ in the procedure in the
|
||
|
|
text, comparing how this will be structured when definitions are interpreted
|
||
|
|
sequentially with how it will be structured if definitions are scanned out as
|
||
|
|
described. Why is there an extra frame in the transformed program? Explain
|
||
|
|
why this difference in environment structure can never make a difference in the
|
||
|
|
behavior of a correct program. Design a way to make the interpreter implement
|
||
|
|
the “simultaneous” scope rule for internal definitions without constructing
|
||
|
|
the extra frame.
|