problem with a foreach loop
I have the following code. After the first foreach loop, I have the data I want in @temp. I've printed it, there are just a lot of dupes. I can't figure out why my second foreach loop isn't getting rid of the dupes. The regex isn't matching $var and I don't get anything on the print.
#!/usr/bin/perl
@vxdisk = `vxdisk -o alldgs list`;
foreach ( @vxdisk ) {
if ( m{.*\d+\s+(\S+)\s+.*} ) {
if ( $1 =~ m{auto} ) {
next;
}
push ( @temp, "\n$1" );
}
}
# Get rid of the dupes
foreach $var ( @temp ) {
if ( !grep( m{$var}, @temp ) ) {
print "$var\n";
# push ( @dg_list, "$var" );
}
}
#print "@dg_list\n";
#!/usr/bin/perl
@vxdisk = `vxdisk -o alldgs list`;
foreach ( @vxdisk ) {
if ( m{.*\d+\s+(\S+)\s+.*} ) {
if ( $1 =~ m{auto} ) {
next;
}
push ( @temp, "\n$1" );
}
}
# Get rid of the dupes
foreach $var ( @temp ) {
if ( !grep( m{$var}, @temp ) ) {
print "$var\n";
# push ( @dg_list, "$var" );
}
}
#print "@dg_list\n";
ASKER
Ok, I figured out I was using the wrong array on the grep, but I'm still getting dupes.
ASKER
Got it!
#!/usr/bin/perl
@vxdisk = `vxdisk -o alldgs list`;
foreach ( @vxdisk ) {
if ( m{.*\d+\s+(\S+)\s+.*} ) {
if ( $1 =~ m{auto} ) {
next;
}
push ( @temp, "\n$1" );
}
}
# Get rid of the dupes
foreach $var ( @temp ) {
if ( !grep( m{$var}, @dg_list ) ) {
# print "$var\n";
push ( @dg_list, "$var" );
}
}
print "@dg_list\n";
#!/usr/bin/perl
@vxdisk = `vxdisk -o alldgs list`;
foreach ( @vxdisk ) {
if ( m{.*\d+\s+(\S+)\s+.*} ) {
if ( $1 =~ m{auto} ) {
next;
}
push ( @temp, "\n$1" );
}
}
# Get rid of the dupes
foreach $var ( @temp ) {
if ( !grep( m{$var}, @dg_list ) ) {
# print "$var\n";
push ( @dg_list, "$var" );
}
}
print "@dg_list\n";
ASKER
If you see a better way to do this, please post it. I'll leave it up for a while.
push ( @dg_list, "$var" ); is commented out, so it will never execute
If there are no meta characters in $var, grep( m{$var}, @temp ) will always succeed
For a better way, you may want to look at
perldoc -q "How can I remove duplicate elements from a list or array"
If there are no meta characters in $var, grep( m{$var}, @temp ) will always succeed
For a better way, you may want to look at
perldoc -q "How can I remove duplicate elements from a list or array"
ASKER
I uncommented it on the second piece of code. It's working now, but if you can see a better way to do it, I'll take it.
ASKER
It also gives me a blank line at the top which I would prefer to get rid of when I print @dg_list. I know it's from the push ( @temp, "\n$1" ), but can't figure out how to get rid of it.
a better way from the perldoc faq
my %seen=();
@dg_list = grep !$seem{$_}++ @temp;
or, if order does not matter
my %seen;
@seen{@temp}=();
print for keys %seen;
my %seen=();
@dg_list = grep !$seem{$_}++ @temp;
or, if order does not matter
my %seen;
@seen{@temp}=();
print for keys %seen;
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ASKER
This is what I get from the first one and the code is right below it.
testbox-[root]/home/share/
Array found where operator expected at vxdisk_chk line 14, near "++ "
(Missing operator before ?)
syntax error at vxdisk_chk line 14, near "++ @temp"
Execution of vxdisk_chk aborted due to compilation errors.
my %seen=();
@dg_list = grep !$seen{$_}++ @temp=();
print "@dg_list\n";
exit;
testbox-[root]/home/share/
Array found where operator expected at vxdisk_chk line 14, near "++ "
(Missing operator before ?)
syntax error at vxdisk_chk line 14, near "++ @temp"
Execution of vxdisk_chk aborted due to compilation errors.
my %seen=();
@dg_list = grep !$seen{$_}++ @temp=();
print "@dg_list\n";
exit;
@dg_list = grep !$seen{$_}++, @temp;
ASKER
I don't get an error with it now, but @dg_list get nothing in it.
Your other suggestion for getting rid of the blank at the top is great.
Your other suggestion for getting rid of the blank at the top is great.
ASKER
This worked.
%hash = map {$_, 1 } @temp;
print "$_\n" for keys %hash;
Thanks ozo.
%hash = map {$_, 1 } @temp;
print "$_\n" for keys %hash;
Thanks ozo.
ASKER