perl中基本变量的转换《1》

基本变量（整型，浮点数，字符串）之间可以相互转换，默认都是“”，即空字符。

　　字符串转换成数值的规则：如果字符串中存在非数值的字符，则为从左起至第一个非数值的字符。

例子：#!/usr/bin/perl

my $string1="12ff";
my $string2="13ff44";
my $string3="gg";
print $string1 + $string2, "\n";
print $string3 * 5, "\n";

my $string4="12.5ff";
my $string5="13.7ff44";

print $string4 + $string5, "\n";
print $string4 * 5, "\n";

my $num1=55;
my $string6="55";

if ( $num1 eq $string6 ) {
        print "equal", "\n";
} else {
        print "not equal", "\n";
}
my $num2=55.5;
my $string7="55.5";

if ( $num2 eq $string7 ) {
        print "equal", "\n";
} else {
        print "not equal", "\n";
}

if ( $num1 eq $string7 ) {
        print "equal", "\n";
} else {
        print "not equal", "\n";
}

if ( $num2 eq $string6 ) {
        print "equal", "\n";
} else {
        print "not equal", "\n";
}
print 10 / $string3, "\n";

结果：

25
0
26.2
62.5
equal
equal
not equal
not equal
Illegal division by zero at ./test_variable.pl line 44.