iterate the A B C

[ilany]

Hi All,

I am trying to find an English letter to do a net use command.
Since most of the letters are already taken, I need to loop over the A
B C and if one letter is free, I will do net use to it.

Do you have an inteligent way to iterate over abc in perl (and not
create an array of all abcdefgh...) ?

Thanks

Ilan

 

[anno4000]

Hi All,

I am trying to find an English letter to do a net use command.
Since most of the letters are already taken, I need to loop over the A
B C and if one letter is free, I will do net use to it.

Do you have an inteligent way to iterate over abc in perl (and not
create an array of all abcdefgh...) ?

What's wrong with creating a list of the alphabet? It isn't long,
not if it begins with a, b, c... . Here is how I would do it
(untested):

use List::Util qw( first);
my $letter = first { ! is_taken( $_) } 'A' .. 'Z';
die "Can't find a free letter" unless $letter;
# go ahead

You would have to provide the function is_taken(), I have no idea
what "net use" is and how to know if it has "taken" a letter.

Anno

 

[Dr.Ruud]

ilany schreef:

I am trying to find an English letter to do a net use command.
Since most of the letters are already taken, I need to loop over the A
B C and if one letter is free, I will do net use to it.

Do you have an inteligent way to iterate over abc in perl (and not
create an array of all abcdefgh...) ?

C:\> perl -le "print for q{A} .. q{Z}"

See perlop.

 

[ilany]

No need for further assistance.
I got it:

print "All Letters\n";
for $list(C..Z) {
print "$list\n";
}

 

[anno4000]

First, please do not top-post.

No need for further assistance.

Oh yes, there is.

I got it:

print "All Letters\n";
for $list(C..Z) {
print "$list\n";
}

You're running without strict and warnings. The variable $list should
be declared lexical. C and Z shouldn't be barewords. Code in blocks
should be indented.

Anno

 

[a]

First, please do not top-post.


Oh yes, there is.


You're running without strict and warnings. The variable $list should
be declared lexical. C and Z shouldn't be barewords. Code in blocks
should be indented.

Anno

Hi
I would like to iterate multiple set of characters. That is,
a..z, A..Z, 0..9
so how can I do the following?
for $list(A..Z and a..z and 0..9){
print "$list\n";
}
Thanks

 

[Ben Morrow]

Hi All,

I am trying to find an English letter to do a net use command.

[For future reference, some mention of 'Windows' or 'Windows drive
mapping' would have been useful here, for context. A lot of people here
have never heard of 'net use'.]

Note that you can get a list of currently allocated driver letters with
Win32API::File::getLogicalDrives, and you can map a network share to a
system-assigned letter by calling Win32::NetResource::AddConnection with
$Connection (which should really be called $Flags) set to
CONNECT_REDIRECT but no LocalName member in %NETRESOURCE. See also
http://windowssdk.msdn.microsoft.com/en-us/library/ms739056.aspx
which is the function that implements AddConnection.

Ben

 

[Ben Morrow]

Note that you can get a list of currently allocated driver letters with
Win32API::File::getLogicalDrives,

Apologies for replying to myself, but on rereading I've realised that
this reply is completely unsuited to the OP's skill level...

For example, you can get the list you want with

use Win32API::File qw/getLogicalDrives/;

my %assigned = map { s/:\\$//; ($_, 1) } getLogicalDrives;
my @free = grep !$assigned{$_}, A..Z;

# or for just the first free letter

use List::Util qw/first/;

my $free = first { !$assigned{$_} } A..Z;

This is a standard Perl technique for finding set difference. You could
also use e.g. Set::Scalar from CPAN.

Ben