Subroutines

[Ondra]

I would like to know what is do the code below:

sub safe {

my $url = shift;

return 1 if ($url =~ /^(javascript|mailto):/is);

for (@safe) { #*******I cann't understand this
return 1 if ($url =~ /\w+:\/\/((\w|-)+\.)*$_/is);
}
return 0;

}

Thanks a lot

Ondrej

 

[Brad Baxter]

I would like to know what is do the code below:

sub safe {

my $url = shift;

return 1 if ($url =~ /^(javascript|mailto):/is);

for (@safe) { #*******I cann't understand this
return 1 if ($url =~ /\w+:\/\/((\w|-)+\.)*$_/is);
}
return 0;

}

It looks to me like the _intention_ is to verify whether a url matches a
set of 'safe' urls (presumably stored in @safe). However, I'm not
confident the code above does that very well.

Regards,

Brad

 

[Tad McClellan]

I would like to know what is do the code below:

I will assume your interest is as a learning exercise, because
it is amateurish and crufty code, I wouldn't trust it.

sub safe {

my $url = shift;

return 1 if ($url =~ /^(javascript|mailto):/is);

I lose confidence in a programmer when they throw do-nothing
options on willy-nilly. The //s does nothing when used with
that pattern, so it should not be there.

Whoever wrote this didn't really understand what they were doing.

for (@safe) { #*******I cann't understand this

It does the same as these:

for $_ (@safe)
foreach (@safe)
foreach $_ (@safe)


See the "Foreach Loops" section in perlsyn.pod.

return 1 if ($url =~ /\w+:\/\/((\w|-)+\.)*$_/is);

//s does nothing yet again.

//i doesn't do anything either!

}
return 0;

}

It appears that @safe holds "approved" TLDs or something. The code
attempts to return true for those domains.

It does it badly. If @safe contains "com", it will match (return true)
when $url = "http://www.company" ...

Send that code to the bit bucket, where it belongs.

 

[Anno Siegel]

I would like to know what is do the code below:

I will assume your interest is as a learning exercise, because
it is amateurish and crufty code, I wouldn't trust it.
[...]

return 1 if ($url =~ /\w+:\/\/((\w|-)+\.)*$_/is);

//s does nothing yet again.

//i doesn't do anything either!

I completely agree with your overall assessment, but /i may do something
here, depending on $_.

Anno