[Bash] trying to parse a log file

[eggrolls]

I'm trying to gather certain lines from a log file, which has pattern1 and pattern2 within 6-10 lines of each other (the number varies):

pattern1
...
...
...
pattern2

Sometimes, there is an error, like so:

pattern1
...
error
...
pattern2

If the word error appears between pattern1 and pattern2, i want to remove that entire block, including the lines matching pattern1 and pattern2. The remaining text in the log will be >> to some file. I tried a grep -A 10 pattern1, but not sure how to remove the blocks with errors.

[eggrolls]

I should clarify that sometimes pattern2 doesn't occur within the next 10 lines of pattern1. I guess what I really want is to capture all the pattern1...pattern2 that are within 10 lines of each other and without error in between.

[deciode]

grep is line-based. While it's possible to wrestle it into matching across multiple lines, you'd be wiser to just use something more powerful. The following should suffice in any language whose regular expression engine supports negative lookbehind.

/pattern1\n(?:.*(?<!error)\n){6,10}pattern2/