My post at Re^2: Replace commas with spaces between quotes, parsing CSV shows a very weird grep statement from another poster. Normally a grep is a simple filter (yes/no), This statement appears to do a substitution and "work" albeit with run-time warnings. I am wondering why it even works as well as it does?

I re-coded this so that there are no warning and my code works as expected. I did have trouble with making this into a map{} instead of foreach(). Performance wise that doesn't matter. But to understand the syntax issues, any ideas?

In reply to Why does this "bad" grep work so well? by Marshall

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