Well I was coding for too long at one time again and I made a silly mistake that had me scratching my head.
I had:
my @array = ('red','green','blue');
print @array . "\n";

[download]
But it was printing '3' instead of what I thought it should which is 'redgreenblue'
Since it was inside a loop I thought it might be a scoping issue. I poked around a bit and finally I took a break. Then it occured to me, "Comma not period!".
So I changed to the code to read:
my @array = ('red','green','blue');
print @array , "\n";

[download]

And everything is fine, well almost.
Its bugging my why it was returning the number of elements instead of nothing or an error. It is my assumption that the '.' forces the variable to be printed in a scalar context instead of as a list. I also assume that the ',' is simply adding a element to the list since ',' is a list seperator character. I found something in the Camel book in the Efficiency section, but it only explained that the ',' is faster in some cases when doing a concatenation. I never really gave this much thought until I used the wrong concatenation character.

What book can I refer to for a detailed explaination?
Are my assumptions correct?

In reply to Period vs. Comma concatenation and reference material for it by trs80

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