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diff --git a/js/games/nluqo.github.io/~bh/ssch1/part1.html b/js/games/nluqo.github.io/~bh/ssch1/part1.html new file mode 100644 index 0000000..6b80283 --- /dev/null +++ b/js/games/nluqo.github.io/~bh/ssch1/part1.html @@ -0,0 +1,84 @@ +<P> + +<P> +<HTML> +<HEAD> +<TITLE>Simply Scheme: Introducing Computer Science, Part 1: Introduction: Functions</TITLE> +</HEAD> +<BODY> +<CITE>Simply Scheme:</CITE> +<CITE>Introducing Computer Science</CITE> 2/e Copyright (C) 1999 MIT +<H2>Part I</H2> +<H1>Introduction: Functions</H1> + +<TABLE width="100%"><TR><TD> +<IMG SRC="../simply.jpg" ALT="cover photo"> +<TD><TABLE> +<TR><TD align="right"><CITE><A HREF="http://www.cs.berkeley.edu/~bh/">Brian +Harvey</A><BR>University of California, Berkeley</CITE> +<TR><TD align="right"><CITE><A HREF="http://ccrma.stanford.edu/~matt">Matthew +Wright</A><BR>University of California, Santa Barbara</CITE> +<TR><TD align="right"><BR> +<TR><TD align="right"><A HREF="../pdf/ssch01.pdf">Download PDF version</A> +<TR><TD align="right"><A HREF="../ss-toc2.html">Back to Table of Contents</A> +<TR><TD align="right"><A HREF="../ssch0/ack.html"><STRONG>BACK</STRONG></A> +chapter thread <A HREF="showing.html"><STRONG>NEXT</STRONG></A> +<TR><TD align="right"><A HREF="http://mitpress.mit.edu/0262082810">MIT +Press web page for <CITE>Simply Scheme</CITE></A> +</TABLE></TABLE> + +<HR><BIG> + +<P>The purpose of these introductory pages before each part of the book is to +call attention to a big idea that runs through all the work of several +chapters. In the chapters themselves, the big idea may sometimes be hidden +from view because of the technical details that we need to make the idea +work. If you ever feel lost in the forest, you might want to refer back +here. + +<P>In these first two chapters, our goal is to introduce the Scheme programming +language and the idea of using <EM>functions</EM> as the building blocks of a +computation. + +<P>The first chapter is a collection of short Scheme programs, presented to +show off what Scheme can do. We'll try to explain enough of the mechanism +so that you don't feel completely mystified, but we'll defer the +details until later. Our goal is not for you to feel that you could +re-create these programs, but rather that you get a sense of what <EM>kinds</EM> of programs we'll be working with. + +<P>The second chapter explores functions in some detail. Traditionally, +computer programs are built out of <EM>actions:</EM> First do this, then do +that, and finally print the results. Each step in the program <EM>does</EM> +something. Functional programming is different, in that we are less +concerned with actions and more concerned with values. + +<P>For example, if you have a pocket calculator with a square root button, you +could enter the number 3, push the button, and you'll see something like +1.732050808 in the display. How does the calculator know? There are +several possible processes that the calculator could carry out. One +process, for example, is to make a guess, square it, see if the result is +too big or too small, and use that information to make a closer guess. +That's a sequence of actions. But ordinarily you don't care what actions +the calculator takes; +what interests you is that you want to apply the +square root <EM>function</EM> to the <EM>argument</EM> 3, and get back a <EM>value.</EM> We're going to focus on this business of functions, arguments, and +result values. + +<P>Don't think that functions have to involve numbers. We'll be working with +functions like "first name," "plural," and "acronym." These functions +have words and sentences as their arguments and values. + +<P> +</BIG> +<HR> +<P><A HREF="../ss-toc2.html">(back to Table of Contents)</A><P> +<A HREF="../ssch0/ack.html"><STRONG>BACK</STRONG></A> +chapter thread <A HREF="showing.html"><STRONG>NEXT</STRONG></A> + +<P> +<ADDRESS> +<A HREF="../index.html">Brian Harvey</A>, +<CODE>bh@cs.berkeley.edu</CODE> +</ADDRESS> +</BODY> +</HTML> |