SICP Exercise 2.3 make-rectangle 2

Exercise 2.3.  Implement a representation for rectangles in a plane. (Hint: You may want to make use of exercise 2.2.) In terms of your constructors and selectors, create procedures that compute the perimeter and the area of a given rectangle. Now implement a different representation for rectangles. Can you design your system with suitable abstraction barriers, so that the same perimeter and area procedures will work using either representation?

 SOLUTION

 In this implementation, the rectangle is constructed given any two sides that share a common end point. If the segments do not satisfy all the required conditions, an error will be reported.


The code and tests are here.

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