fig05_12.pl

PERL语言资料 可以用于PERL程序设计

#!/usr/bin/perl
# Fig. 5.12: fig05_12.pl
# Using bare blocks to form a multiple-selection structure.

print "Enter your guess (1-3): ";
$guess = <STDIN>;

BLOCK: { # start of bare block
   if ( $guess == 1 ) { 
      print "Right!\n"; 
      last BLOCK;       # jump to end of BLOCK
   }

   if ( $guess == 2 ) { 
      print "Close!\n"; 
      last BLOCK;       # jump to end of BLOCK
   }

   if ( $guess == 3 ) { 
      print "Wrong!\n"; 
      last BLOCK;       # jump to end of BLOCK
   }

   # default case; executes only if $guess is not 1, 2 or 3
   {
      print "Please re-enter your guess (1-3): "; 
      $guess = <STDIN>; 
      redo BLOCK;       # jump to beginning of BLOCK
   }
} # start of bare block



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