[Feature Request] Support case when end range pattern is not distinct from start pattern

[balki]

[Feature Request] Support case when end range pattern is not distinct from start pattern

[benhoyt]

Yes, this is slightly tricky, isn't it? I'd rather not introduce new syntax and range pattern types above and beyond POSIX here, so I'd suggest not using a range pattern for this, but two patterns with a flag. Similar to your endcond solution but a bit simpler (and one line :-).

You have to be careful with the order of the patterns, putting the /^ts:/ { e=0 } pattern-action first, so that the /Got Excep/ { e=1 } sets e to 1 for that first line before the e { print } pattern is evaluated, and the "Got Exception" line is printed:

$ goawk '/^ts:/ { e=0 }  /Got Excep/ { e=1 }  e { print }' data.txt
ts:Jan 11 12:16:33 ERROR Got Exception in module foo
                         1. Traceback (most recent call last):
                         1.   File "/tmp/teste.py", line 9, in <module>
                         1.     run_my_stuff()
                         1. NameError: name 'run_my_stufff' is not defined
ts:Jan 11 12:17:33 ERROR Got Exception in module foo
                         2. Traceback (most recent call last):
                         2.   File "/tmp/teste.py", line 9, in <module>
                         2.     run_my_stuff()
                         2. NameError: name 'run_my_stufff' is not defined

You can even shorten it slightly more by dropping the { print } on the last pattern, as that's the default:

$ goawk '/^ts:/ { e=0 }  /Got Excep/ { e=1 }  e' data.txt

The Gawk manual also has a couple of examples for range patterns that might be useful (though they don't quite fit what you're doing here).

Hope that helps!

[balki]

Thanks! Though not obvious at first glance, yet concise and clear.

$ goawk '/^ts:/ { e=0 }  /Got Excep/ { e=1 }  e' data.txt