This week's worksheet👇

mentor11.pdf

mentor11_sol.pdf

Scheme concept review

Useful links:

https://cs61a.org/articles/scheme-builtins/

https://cs61a.org/articles/scheme-spec/

Primitives

• Primitives evaluate to themselves.
  • scm> True → True
  • scm> 3 → 3

Call expressions *prefix notation in scheme

Form: (operator operand operand)

1. Evaluate operator and operands from left to right
2. Apply operator value on operand values

Special forms: define variables

• looks like a call expression
• don't evaluate the first operand (the variable)
• evaluates to the variable name

scm> (define x 5)

x

scm> (define y (+ x 4)