Re: Beginner : delete a line with repeating pattern

> echo "house boat car, , , ," | sed '/, \{4\}$/d' this works (4
> commas in a row)

I don't think that this does what you expect it to.  It doesn't find 4 commas in a row, if finds a comma followed by 4 spaces at the end of the line, and deletes the whole row if it finds that.

> How do I deal with 
> echo "house boat car, , , , $"    a comma followed by a space 4 times. I tried the [ ] but it didnt work
> echo "house boat car, , , ," | sed '/[, ]\{4\}$/d'
> echo "house boat car, , , , " | sed '/, \{4\}$/d'

I *think* what you want is 4 "comma + zero or more spaces" which
should be something like

  echo "house boat car, , , , " | sed '/\(, *\)\{4\}$/d'

If you just want to remove the commas/spaces while keeping the first
value, you can do

  echo "house boat car, , , , " | sed 's/\(, *\)\{4\}$//'

-tim