Lecture 3 - Page 5 : 42
Functional Programming in Scheme
Name binding, Recursion, Iteration, and Continuations
* Name binding constructs
The
let
name binding expression
The equivalent meaning of
let
Examples with
let
name binding
The
let*
name binding construct
An example with
let*
The
letrec
namebinding construct
LAML time functions
* Conditional expressions
Conditional expressions
Examples with
if
Example with
cond
:
leap-year?
Example with cond:
american-time
Example with
cond
:
as-string
* Recursion and iteration
Recursion
List processing
Tree processing (1)
Tree processing (2)
Recursion versus iteration
Example of recursion:
number-interval
Examples of recursion: string-merge
Examples with recursion:
string-of-char-list?
Exercises
* Example of recursion: Hilbert Curves
Hilbert Curves
Building Hilbert Curves of order 1
Building Hilbert Curves of order 2
Building Hilbert Curves of order 3
Building Hilbert Curves of order 4
A program making Hilbert Curves
* Continuations
Introduction and motivation
The catch and throw idea
A catch and throw example
The intuition behind continuations
Being more precise
The capturing of continuations
Capturing, storing, and applying continuations
Use of continuations for escaping purposes
Practical example: Length of an improper list
Practical example: Searching a binary tree
The
let*
name binding construct
It is often useful to be able to use previous name bindings in a let construct, which binds several names
(let* ((n
1
e
1
) ... (n
i-1
e
i-1
) (n
i
e
i
) ... (n
k
e
k
)) body-expr)
Characteristics of
let*
:
It is possible to refer to n
1
through n
i-1
from the expression e
i
Syntactic sugar for k nested
let
name bindings
