view release on metacpan or  search on metacpan

t/data/cs61.anki  view on Meta::CPAN

`


#csnip
```
(first (bf '(a hard days night)))
```

evaluate to "hard"

`


#csnip
```
(first (first (bf '(she loves you))))
```

evaluates to "l"

`


#csnip
```
(define pi 3.14)
(* pi 5 5)
```

The first line sets the value of `pi` to 3.14. The second line multiplies `pi`
by 25 (5 * 5).

`


#csnip
```
(define (square x)
    (* x x)
(square (+ 2 3))
```

It defines a function called `square` that takes a single argument called `x`.
The body of the function takes `x` and multiplies it by itself. The third line
calls the `square` function with result of the express `2 + 3` (or 5), which
returns an answer of 25 (5 squared).

`


#basic
Why is the `define` function considered an exception to the way scheme normally
processes arguments?

Because it does not evaluate the arguments that are passed to it.

`


#basic
Describe what we mean when we say a function is a *special form* function?

It is a function that does not process arguments the way other scheme functions
do. The `define` function is an example.

`


#cquest
What does the following code evaluate to and why?

```
(define hello (+ 2 3))
hello
```

The first line evaluates the word "hello," the function that was defined. It
does not evaluate to "5" because `define` does not evaluate its arguments. The
second line evaluates to 5, the result of the expression, 2 + 3.

`


#cquest
What is the code in bold referred to as?

```
(define (square <b>x</b>)
    (* x x)
(square (+ 2 3))
```

the formal parameter, the argument that is passed to the function

`



#cquest
What is the code in bold referred to as?

```
(define (square x)
    <b>(* x x)</b>
(square (+ 2 3))
```

the body

`



#cquest
What is the code in bold referred to as?

```
(define (square x)
    <b>(* x x)</b>
(square <b>(+ 2 3)</b>)
```