(crazyinsomniac) Re: What is the difference between a list and an array?

A list is, well, just that, a list, a bunch of values separated by commas. An array is a data structure -- a "variable".

Consider this:

for my $thing("this","Is","aA","List")
{
  print "$thing\n";
}

print "\---------\n";

my @things = ("this","Is","aA","List","being","assigned","to","an","ar
+ray");

for my $thing(@things)
{
  print "$thing\n";
}

print "\---------\n";

my %things = ("this", "Is",
              "aA", "List",
              "being", "assigned",
              "to", "a",
              "hash", "and",
              "as", "such",
              "it", "must",
              "be", "EVEN!",
             ,);

for my $thing(@things)
{
  print "$thing\n";
}
[download]

Furthermore, the distinction between a list and an array goes to context. There are two context's in perl, list, and scalar. The scalar function forces scalar context. The for (@something) "construct" implies list construct, as do functions and other things. To get a better grip on context in perl, please read japhys excellent article from perlmonth.com Issue 9: "List" is a Four-Letter Word (local) (remote).

___crazyinsomniac_______________________________________
Disclaimer: Don't blame. It came from inside the void
perl -e "$q=$_;map({chr unpack qq;H*;,$_}split(q;;,q*H*));print;$q/$q;"

Comment on (crazyinsomniac) Re: What is the difference between a list and an array? Download Code

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Re(2) (crazyinsomniac): What is the difference between a list and an array? by dmmiller2k (Chaplain) on Dec 12, 2001 at 00:38 UTC
A list is, well, just that, a list, a bunch of values separated by commas. You may be failing to address the confusion between what a list is with its literal representation in a program. After all a "bunch of values separated by commas" is considered a list literal, where the commas are mere notational conveniences. To the program itself, a list is a series of values, nevermind how they got there. This is NOT a flame! It goes more to highlighting the difference between what a thing is (e.g., list), and what you have to write in a program to get one. This particular distinction (or more precisely, the failure to understand it) caused more problems for me early on than maybe anything else (one exception: learning that `my` means `local`--in the C/C++ sense of the word--and that `local` really means localized `global`, or having a temporary local value for one But I digress). Fortunately for me, Perl's forgiving nature (combined with its uncanny "do what I mean" quality) saved my skin more than once. But when I later went back to examine some of my old code, I could see evidence of my then-incomplete understanding of these concepts. dmm You can give a man a fish and feed him for a day ... Or, you can teach him to fish and feed him for a lifetime	[reply] [d/l] [select]
Re(2): (crazyinsomniac): What is the difference between a list and an array? by dmmiller2k (Chaplain) on Dec 13, 2001 at 00:02 UTC
crazyinsomniac: Truly, I meant no harm, in "Re(2) (crazyinsomniac): What is the difference between a list and an array?," above. Please consider it an (apparently unsuccessful) attempt at constructive criticism. I was hoping to articulate how your explanation might have perhaps obfuscated more than illuminated the subject for me, given my own understanding (or lack thereof) back when I was struggling with this concept myself, and in so doing, perhaps assist sierrathedog04 (et al) in that endeavor. dmm You can give a man a fish and feed him for a day ... Or, you can teach him to fish and feed him for a lifetime	[reply]


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