关于perl中的my， our的用法自己一直都是一知半解的。以至于基本上在程序中把所有的变量的前面都加上my， 省事还不报错!
I am still not familiar the concept, but I will list some examples here to add as a reminder.
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| our $var = 1;
{
our $var = 2;
print "$var\n";
}
print "$var\n";
|
It will give us the result:
If the code looks like this:
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6
| my $var = 1;
{
my $var = 2;
print "$var\n";
}
print "$var\n";
|
It will give us the result:
If the code is:
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| our $var = 1;
{
my $var = 2;
print "$var\n";
}
print "$var\n";
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It will give us the following result:
if the code is:
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6
| my $var = 1;
{
our $var = 2;
print "$var\n";
}
print "$var\n";
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It will give us the result:
If the code is one of the following, it will give us the result 2:
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| my $var = 1;
my $var = 2;
print $var, "\n";
our $var = 1;
our $var = 2;
print $var, "\n";
my $var = 1;
our $var = 2;
print $var, "\n";
our $var = 1;
my $var = 2;
print $var, "\n";
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I still can not claim I understand my and our.
We will give more examples on this.
The following 3 code snippets will give us the result (1, 6, 11):
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| my $i = 0;
for ($i = 1; $i<10; $i++){
print $i, "\n";
$i = $i + 4;
}
print $i, "\n";
#1,6,11
our $i = 0;
for ($i = 1; $i<10; $i++){
print $i, "\n";
$i = $i + 4;
}
print $i, "\n";
#1,6,11
our $i = 0;
for (our $i = 1; $i<10; $i++){
print $i, "\n";
$i = $i + 4;
}
print $i, "\n";
#1,6,11
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While the following 3 will give us the result (1, 6, 0):
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| my $i = 0;
for (my $i = 1; $i<10; $i++){
print $i, "\n";
$i = $i + 4;
}
print $i, "\n";
#1,6,0
my $i = 0;
for (our $i = 1; $i<10; $i++){
print $i, "\n";
$i = $i + 4;
}
#1,6,0
our $i = 0;
for (my $i = 1; $i<10; $i++){
print $i, "\n";
$i = $i + 4;
}
print $i, "\n";
#1,6,0
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