Question 1 @ 2024-10-08 18:25

Which of the following are true about different treatments of functions in programming languages?

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• FOV

  First order: functions can be used as values

• FOS

  First order: function values can be created in any scope

• HOV

  Higher order: functions can be used as values

• HOS

  Higher order: function values can be created in any scope

• FCV

  First class: functions can be used as values

• FCS

  First class: function values can be created in any scope

Question 2 @ 2024-10-08 18:28

What expressions are in the scope of the first y in this expression:

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• 0 The question is bogus, we cannot distinguish just the first y.
• E1 E1
• E2 E2
• E3 E3
• E4 E4
• E5 E5

Question 3 @ 2024-10-08 18:30

What is the result of the following Interactive Falsification (IF) expression from HW#4?

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• Ew Error: You cannot have a with expression inside an `if’
• Ex Error: The there is a free x identifier
• Ey Error: The there is a free y identifier
• T #t
• F #f
• 1 1

Question 4 @ 2024-10-08 18:34

At some point we had the following broken bit of code in our implementation of subst:

Which one of the following tests can be used to demonstrate the bug in this code fragment?

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• A {with {x x} ...}
• B {with {x x} {with {x 3} ...}}
• C {with {x 3} {with {x x} ...}}
• D {with {x 3} {with {y x} ...}}
• E {with {y 3} {with {x y} ...}}

Question 5 @ 2024-10-08 18:38

What are we going to do today?

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• A

  Optimize our language using native-code compilation.

• B

  Improve our asymptotically horrible function call costs.

• C

  Implement third-order functions.

• D

  Implement object orientedness in our language.

• E

  Add a type checker.