I am not getting "<>" diamond operator right. I want to understand how the "<>" (empty Diamond operator)" works in a "while"loop.

Here is my code ( the script is saved as diamond.pl): 

#!/usr/bin/perl -w
while (<>)
{
    print ;
}

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Now i have two files called colors.txt and seasons.txt in the same directory as that of the above script. so if i run below command, it start printing the individual lines of both the .txt files: 

perl diamond.pl colors.txt seasons.txt

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and I understand above.

However, If I run below comamnds, it errors out; 

perl diamond.pl these are words and not the file names

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I get below eerror: 

# perl diamond.pl these are words and not the file names
Can't open these: No such file or directory at diamond.pl line 2.
Can't open are: No such file or directory at diamond.pl line 2.
Can't open words: No such file or directory at diamond.pl line 2.
Can't open and: No such file or directory at diamond.pl line 2.
Can't open not: No such file or directory at diamond.pl line 2.
Can't open the: No such file or directory at diamond.pl line 2.
Can't open file: No such file or directory at diamond.pl line 2.
Can't open names: No such file or directory at diamond.pl line 2.

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My undestanding was (and this is mentioned on numerous pages on hte internet), the empty "<>" checks for the @ARGV. So in above command, I was hoping to see the output as one word of the sequence "these are words and not the file names" printed on each line.

I am pretty sure am doing something really dumb here. could you explain how an "<>" (empty) operators works in a while loop. An example of the script and the command would be of great help.

Thanks.

In reply to How to use empty "<>" (Diamond Operator) inside While loop by slayedbylucifer

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