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Now we arrive at the while loop. A loop not to be taken lightly. If you ever see your program perpetually executing something, a while loop is most likely the culprit. I have lost count how many times I have stared at the screen when it was scrolling lines and lines of data endlessly forever when only a couple of times was necessary. You guessed it - a badly written while loop.
Syntaxwhile ( condition ) {
body
}
Execute script repeatedly as long as a given condition is true. OK! Here comes the example...
#!/usr/local/bin/perl print "Top 10 Surprises in Windows 2000\n\n"; #Make a list of surprises my @surprises = ( "You get $10 off if you voluntarily give them your soul, but it's full price if they have to force it out of you.", "It is still possible to fix a sandwich and something to drink while waiting for Start Up.", "When you peel off the label on the CD, there's Window'95 label under it.", "To open Netscape : Press ctrl d, alt 4, tab, tab, spell Nebraska backwards and press enter, enter your gender, compose a 500-word essay.... ", "Entering \"Department of Justice\" into Organization Field during set-up will crash system" , "New app monitors Bill Gates's wealth for you to see" , "Mix-up in shipping department sends a dog named \"Bowser\" with every copy" , "A \$1 off coupon for Mrs Smith's cream pie with Bill's home address on back" , "Includes sample bugs from upcoming Windows 2000 Advanced Server!" , "Surgeon General has put a warning on Solitaire that repeated use may be habit forming."); my $no=10; while ($no > 0) { print "Surprise $no : $surprises[$no-1]\n"; $no = $no - 1; }
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