@@ -72,35 +72,42 @@ \chapter*{Front Matter\label{front}}
7272
7373\chapter {Whetting Your Appetite \label {intro } }
7474
75- If you ever wrote a large shell script, you probably know this
76- feeling: you'd love to add yet another feature, but it's already so
77- slow, and so big, and so complicated; or the feature involves a system
78- call or other function that is only accessible from C\ldots \ Usually
79- the problem at hand isn't serious enough to warrant rewriting the
80- script in C; perhaps the problem requires variable-length strings or
81- other data types (like sorted lists of file names) that are easy in
82- the shell but lots of work to implement in C, or perhaps you're not
83- sufficiently familiar with C.
84-
85- Another situation: perhaps you have to work with several C libraries,
86- and the usual C write/compile/test/re-compile cycle is too slow. You
87- need to develop software more quickly. Possibly you've
88- written a program that could use an extension language, and you don't
89- want to design a language, write and debug an interpreter for it, then
90- tie it into your application.
91-
92- In such cases, Python may be just the language for you. Python is
93- simple to use, but it is a real programming language, offering much
94- more structure and support for large programs than the shell has. On
95- the other hand, it also offers much more error checking than C, and,
96- being a \emph {very-high-level language }, it has high-level data types
97- built in, such as flexible arrays and dictionaries that would cost you
98- days to implement efficiently in C. Because of its more general data
99- types Python is applicable to a much larger problem domain than
100- \emph {Awk } or even \emph {Perl }, yet many things are at least as easy
101- in Python as in those languages.
102-
103- Python allows you to split your program in modules that can be
75+ If you do much work on computers, eventually you find that there's
76+ some task you'd like to automate. For example, you may wish to
77+ perform a search-and-replace over a large number of text files, or
78+ rename and rearrange a bunch of photo files in a complicated way.
79+ Perhaps you'd like to write a small custom database, or a specialized
80+ GUI application, or a simple game.
81+
82+ If you're a professional software developer, you may have to work with
83+ several C/\Cpp /Java libraries but find the usual
84+ write/compile/test/re-compile cycle is too slow. Perhaps you're
85+ writing a test suite for such a library and find writing the testing
86+ code a tedious task. Or maybe you've written a program that could use
87+ an extension language, and you don't want to design and implement a
88+ whole new language for your application.
89+
90+ Python is just the language for you.
91+
92+ You could write a {\UNIX } shell script or Windows batch files for some
93+ of these tasks, but shell scripts are best at moving around files and
94+ changing text data, not well-suited for GUI applications or games.
95+ You could write a C/{\Cpp }/Java program, but it can take a lot of
96+ development time to get even a first-draft program. Python is simpler
97+ to use, available on Windows, MacOS X, and {\UNIX } operating systems,
98+ and will help you get the job done more quickly.
99+
100+ Python is simple to use, but it is a real programming language,
101+ offering much more structure and support for large programs than shell
102+ scripts or batch files can offer. On the other hand, Python also
103+ offers much more error checking than C, and, being a
104+ \emph {very-high-level language }, it has high-level data types built
105+ in, such as flexible arrays and dictionaries. Because of its more
106+ general data types Python is applicable to a much larger problem
107+ domain than Awk or even Perl, yet many things are at
108+ least as easy in Python as in those languages.
109+
110+ Python allows you to split your program into modules that can be
104111reused in other Python programs. It comes with a large collection of
105112standard modules that you can use as the basis of your programs --- or
106113as examples to start learning to program in Python. Some of these
@@ -115,8 +122,8 @@ \chapter{Whetting Your Appetite \label{intro}}
115122It is also a handy desk calculator.
116123
117124Python enables programs to be written compactly and readably. Programs
118- written in Python are typically much shorter than equivalent C or
119- \Cpp {} programs, for several reasons:
125+ written in Python are typically much shorter than equivalent C,
126+ \Cpp {}, or Java programs, for several reasons:
120127\begin {itemize }
121128\item
122129the high-level data types allow you to express complex operations in a
@@ -145,7 +152,8 @@ \chapter{Whetting Your Appetite \label{intro}}
145152
146153Now that you are all excited about Python, you'll want to examine it
147154in some more detail. Since the best way to learn a language is
148- to use it, you are invited to do so with this tutorial.
155+ to use it, the tutorial invites you to play with the Python interpreter
156+ as you read.
149157
150158In the next chapter, the mechanics of using the interpreter are
151159explained. This is rather mundane information, but essential for
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