Monks,
I am trying to edit a CSV string, where my goal is to insert a character (a zero) between any occurrence of two consecutive commas. In other words, I'm replacing any missing values with a zero, e.g., 
1,2,,4 -> 1,2,0,4
The regex I have written does not work as I expected, so I have two questions:
1) What regex would accomplish this, and
2) What is wrong with my approach. There's some subtlety of regexs that I need to familiarize myself with!

This code: 

$s="1,2,3,,5,6,,,9,10,,,,14,15,,,,,,,,,,,,,"; $s=~s/,,/,0,/g; 
print "$s\n"; '
...results in : 
1,2,3,0,5,6,0,,9,10,0,,0,14,15,0,,0,,0,,0,,0,,0,,

Thanks for considering this issue!
{}think; #Think outside of the brackets

In reply to Regex to replace consecutive tokens by {}think

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