Re: process array with while loop

my @array = qw(blue red orange brown);  # No commas in qw()

foreach (@array) {
   print("$_\n");
}
[download]

<...> is used when reading from a file handle. It can also be used for globbing (as you are using it), but that's very fragile.

Update: Just noticed the commas in qw(). Addressed this.

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Re^2: process array with while loop by jbert (Priest) on Nov 09, 2006 at 18:44 UTC
To elaborate (because this foxed me, I thought <> must have different behaviour when passed an array), as far as I can tell, the reason this appears to work is a result of: `glob("pattern")` returns "pattern" if no files match the pattern (this includes patterns which no metacharacters, such as 'blue'); In a scalar context `<pattern>` is magic - it keeps state and returns each successive value of glob("pattern"). For example, create files `touch tt1 tt2 tt3` and then run: `print scalar <tt?>, "\n" for 1..3; # prints tt1, tt2 and tt3` [download] Note that (like the flipflop operator) each seperate instance of `<pattern>` appears to keep its own internal state. `print scalar <tt?>, "\n"; print scalar <tt?>, "\n"; print scalar <tt?>, "\n"; # prints tt1, tt1, tt1` [download] And to drive the point home, fun with closures: `my $s = sub { return scalar <tt?>; }; print $s->(), "\n"; print $s->(), "\n"; print $s->(), "\n"; # prints tt1, tt2, tt3` [download] So...this will "work" provided none of the array elements is a string which both contains a glob metacharacter and matches a file as a glob. (If the array elt doesn't contain any such chars, it doesn't matter if it matches or not - you'll get back the pattern).	[reply] [d/l] [select]

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Re^2: process array with while loop
by jbert (Priest) on Nov 09, 2006 at 18:44 UTC

glob("pattern") returns "pattern" if no files match the pattern (this includes patterns which no metacharacters, such as 'blue');
In a scalar context <pattern> is magic - it keeps state and returns each successive value of glob("pattern"). For example, create files touch tt1 tt2 tt3 and then run:
```
print scalar <tt?>, "\n" for 1..3;
# prints tt1, tt2 and tt3
[download]
```
Note that (like the flipflop operator) each seperate instance of <pattern> appears to keep its own internal state.
```
print scalar <tt?>, "\n";
print scalar <tt?>, "\n";
print scalar <tt?>, "\n";
# prints tt1, tt1, tt1
[download]
```
And to drive the point home, fun with closures:
```
my $s = sub { return scalar <tt?>; };
print $s->(), "\n";
print $s->(), "\n";
print $s->(), "\n";
# prints tt1, tt2, tt3
[download]
```