Regex to delete consecutive lines with a specific symbol

Question

I have a huge text file to sort and I noticed that the lines I don't need usually come with a hyphen - symbol and more than 3 lines in a row. So I want to use regex to remove these lines.

I tried this: ^.*(?:\-.*?){3}.*(?:\R|\Z) but it works only within a single line while I need to remove only consecutive lines with - starting from 3 and more.

Example of my text:

Good Line 1
Error-1
Error-2:3045
Error-3-32
Good Line 2
Error-4_sub
Error-5.0
Error-6...0
Error-7
Error-8-9
Error-9
Good Line 3

desired output

Good Line 1
Good Line 2
Good Line 3

Answer 1

• Ctrl+H
• Find what: (?:^.*?-.*(?:\R|\z)){4,}
• Replace with: LEAVE EMPTY
• CHECK Wrap around
• CHECK Regular expression
• UNCHECK . matches newline
• Replace all

Explanation:

(?:                 # Beginning non capture group
^                   # beginning of line
  .*?               # 0 or more any character but newline, not greedy
  -                 # hyphen
  .*                # 0 or more any character but newline
  (?:\R|\z)         # non capture group, any kind of linebreak OR end of file
){4,}               # end group, must appear 4 or more times
                        # set the value to your needs

Screenshot (before):

Screenshot (after):

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