|
Dear
Intro to Programming Attendee --
Welcome
aboard! In order for the tutorial to run smoothly,
you should install Perl and ensure that it works prior
to the tutorial. (Note that this is not a requirement
-- if you don't have a laptop with you you can still
learn some programming, but you won't have as much
fun, and will not learn as much.)
After
installing Perl (or if you already have it installed),
you should ensure that it's working properly, and
that you know how to run it. I will have a few sample
program and data files for to download, too.
Please
write to me by mid-week and let me know both what
kind of system you're using, and how succesful you
have been at getting Perl to run on it.
I
am not an expert on installing things in general,
let alone Perl, but here are some brief instructions
to get you started.
Note
that CPAN, a site listed below from which to get Perl,
has lots of mirror sites. See http://www.perl.com/CPAN-local/SITES.html.
GNU/Linux
If
you have a GNU/Linux system, the odds are reasonably
high you already have Perl. Try the command
perl -v
if
you get version information that tells you you're
running Perl 5.xx (I'm running 5.005_02), you're good
to go. If you get a "command not found" error message,
you'll need to install Perl. You can install from
source, or if you're lucky, there will be a binary
available for your system. Both are available from
http://www.ActiveState.com/Products/ActivePerl/. You
will also need a text editor. I don't know of any
GNU/Linux system that does not have either vi or emacs.
Both are excellent editors, although I cannot help
you with vi at all.
After
you've ensured you have Perl, make sure you can get
it to work. Obtain or write the hello_world.perl program
(found below in this mail). Then try to execute it
both from a perl commandline (perl hello_world.perl)
and, after setting it to be an executable file (chmod),
as a command itself (you may need to change your PATH
environment variable or enter the entire path to the
perl program).
Macintosh
Two
possible setups:
* MPW (Macintosh Programmer's Workshop) and MacPerl
for MPW.
* Alpha or BBEdit and MacPerl. (You could use a different
text editor, but these are the only two that I know
of that will do syntax coloring, run Perl scripts
on their buffers, and some other cool things.)
I'm guessing if you use MPW you don't need any instructions
from me, except where to get MacPerl -- you'll need
both of the following:
http://www.perl.com/CPAN-local/ports/mac/Mac_Perl_520r4_appl.bin
http://www.perl.com/CPAN-local/ports/mac/Mac_Perl_520r4_tool.bin
Alpha
is a $30 shareware text editor that is very powerful,
and integrates quite well with MacPerl, but does not
have a particularly friendly interface, and occasionally
crashes my Mac. It can be obtained from http://alpha.olm.net/.
The current released version is 7.2 (click on "downloads");
I use the pre-release 7.3 (link is near the bottom
of the page).
BBEdit
is a roughly $100 commercial text editor that is very
also powerful, and particularly well suited for HTML.
It is somewhat more "Mac-like", better documented,
and easier to use in general than Alpha, but is not
as well integrated with MacPerl. I use 4.5; the MacPerl
integration is better (but still not as good as Alpha's)
in the current version, 5.1.1.
There
is a free version "BBEdit Lite", which integrates
as well as 4.5, but does not do syntax coloring, and
is missing several other useful features. Both are
vailable from http://www.barebones.com/.
Whichever
editor you use, you only need to install the MacPerl
application (you can get it from http://www.perl.com/CPAN-local/ports/mac/Mac_Perl_520r4_appl.bin)
One can usually get away with only the default settings.
MacPerl knows which editor you are using by the "editor"
setting chosen in the "Helpers" panel of Internet
Config.
To
test that MacPerl works, obtain or write the hello_world.perl
program (found below in this mail), and save it as
a plain text file. >From within MacPerl press CMD-R
(or choose Script > Run Script...), choose the hello_world.perl
program you have just saved.
Windows
I
do not use PCs myself; I did once help a colleague
install Perl (and emacs & bash) on a Windows NT machine,
though. For Windows 3.1, 95, 98, 2K, & NT there is
a port of Perl available at http://www.ActiveState.com/Products/ActivePerl/.
Supposedly
when the Active Perl installer runs it sets your system
so that Windows associates the extension ".pl" with
the Active Perl application -- but I never got that
to work on my colleague's machine.
In
order to use redirection (which will be explained
during the tutorial) you will have to issue perl commands
from a command shell -- DOS and bash are the only
two I know of. Bash has loads of advantages like tab
completion and command history, but DOS has the advantage
of already being on your system (and probably familiarity).
After
installing, you should test that Perl works. Obtain
or write the hello_world.perl program (found below
in this mail). Then try to execute it from a perl
commandline in your shell. Probably something like
C:\Applications\Perl\perl.exe C:\Documents\Perl_Tut\hello_world.prl
You
could also set your environment so that "perl" could
be substituted for the complete path to the perl interpreter
itself, and if you made the directory with your programs
the current directory (e.g., something like cd c:\Documents\Perl_Tut\),
you could skip typing the path to the program file,
too. Theorhetically you should be able to convince
your system to run the program by entering just "hello_world",
but I've yet to get that to work. I do not know how
to run Perl on a Windows system other than via a DOS
or bash shell. (I don't even know if it can be done.)
If anyone figures it out, please let us all know.
---------------
do not include this line in program ---------------
#!
put-your-path-to-perl-here -w
#
#
hello.perl
#
#
Written 2000-07-17 by Syd Bauman as demo of a tiny
Perl program.
# Does nothing except write "Hello, world!" to STDOUT.
#
use strict; # forces more explicit code
use English; # allows clearer special variable names
print "Hello, world!\n"; exit 0;
---------- do not include this line in program, either
----------
Replace "put-your-path-to-perl-here" with the path
to the Perl interpreter. In GNU/Linux this is likely
to be something like "/user/local/bin/perl"; in Windows
it might be something like "C:\Applications\ActivePerl\perl.exe"
(I'm not sure wether or not you should include the
".exe".) In either case, this line is only used if
you try to enter the program as an executable, rather
than specifying the program file as an argument to
the perl command. On a Mac, the "put-your-path-to-perl-here"
is just "perl".
-- Syd Bauman
Syd_Bauman@Brown.edu
401-863-3835
|
