Re^3: GetOpts not working:

[hippo]

There appears to be no benefit to your use of a for loop in that code. Standard hash population means that it isn't needed.

use strict;
use warnings;

my @ARGV = qw(-infile data_in.bin -outfile data_out.bin);

my %args = @ARGV;

print "Infile: $args{-infile}\n", "Outfile: $args{-outfile}" if ( exis
+ts $args{-infile} && exists $args{-outfile} );

works just the same. HTH.

PS. I wouldn't use @ARGV for a lexical variable name since it ordinarily has a special meaning.

[james28909]

I tested it and it does indeed work. How is this possible? How does it know to put the filenames into their respective places? Does it somehow auto assign a key/value pair? Im just as confused lol, because I thought you had to shift the array to get the next value, but somehow it automatically did it :0 This is what i did:

use strict;
use warnings;

my %args = @ARGV;

print "Infile: $args{-infile}\n", "Outfile: $args{-outfile}" if ( exis
+ts $args{-infile} && exists $args{-outfile} );

I fed it '-infile data_in.bin -outfile data_out.bin'. and it almost seems like it has assigned key/value pairs based off of my thought patterns lol <.<

I guess what i am asking is, how did it build the hash? and why did my %args = @ARGV; build it correctly like that. How is 'data_in.bin' and 'data_out.bin' not a key? if key -infile contains value 'data_in.bin' then what assigned 'data_in.bin' to be its value? there was no shifting or anything to loop through the input args

[hippo]

Does it somehow auto assign a key/value pair?

Essentially, yes. When you assign directly to a hash it expects a list of key-value pairs. This is why you sometimes see the warning "Odd number of elements in hash assignment" because the list must be even-sized so that each key has a corresponding value. These two assignments are effectively the same:

my %foo = ( baz => 1, frob => 'quux' );
my %bar = ( 'baz', 1, 'frob', 'quux' );

There's more about this in List value constructors in perldoc.

Does that help?

[james28909]

Awesome. thanks for the link/info. i thought perl was reading my mind for a min there haha