Let Example

(let ((x '(1 2))) (car x))

nil

1

1. Evaluating '(1 2) yields a pointer to a list in memory.

2

2. Extend the environment with a binding for x.

x:

3. Evaluate the body of the let in the new environment.

x evaluates to a pointer to the list, so (car x) evaluates to the first element, namely 1.

current env

4. Restore the old environment.

5. Return the value we got: 1

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