IO 双引号 输出 输入

#! /usr/bin/perl
use strict;
use warnings;

print " ---------<STDIN>_store_into_an_array_and_then_chomp()---------- ";
my @lines = <STDIN>;
chomp(@lines);
print " ---------Input_complete---------- ";
print "@lines";
print " ---------<STDIN>_store_into_an_array_and_then_chomp()---------- ";

print " ----------while_$line__defined_check_EOF--------- ";
my $line;
while (defined($line = <STDIN>)){
    print "I saw $line. ";
}
print " ----------while_$line__defined_check_EOF--------- ";

print " --------while_(<STDIN>)----------- ";
while(<STDIN>){
    print "I saw $_";
}
print " --------while_(<STDIN>)----------- ";

print " -------------------------------while(define($_ = <STDIN>))----------------------------- ";
while(defined($_ = <STDIN>)){
    print "I saw $_";
}
print " -------------------------------while(define($_ = <STDIN>))----------------------------- ";

print " -------------------------------foreach(<STDIN>)----------------------------- ";
foreach(<STDIN>){
    print "Input line is: $_.";
}
print " -------------------------------foreach(<STDIN>)----------------------------- ";





print " ------------------------------------------------------------ ";
print " ------------------------------------------------------------ ";
print " ------------------------------------------------------------ ";
print " ------------------------------------------------------------ ";