Why Does Bash Show an Error on a Valid Command After an Invalid One?

It sounds like you're hitting a weird Bash quirk. When you enter the second command with the escaping, it may result in a syntax issue due to how Bash interprets your input, probably because of the previous error. It doesn't seem to fully reset the state after encountering the first error in your sequence.

Also, the prompt type can change depending on the state of your input; you might want to check if it's switching to PS2, which can indicate an unclosed quote or similar issue. Try to run your commands one at a time, without making editing using the up arrow right away after an error.

A common workaround is to simplify how you're escaping characters. Instead of using `[[ 'a(' == *[(]* ]]`, try just `[[ 'a(' == *(* ]]`. It should work correctly without the extra confusion from the escaping.

It's also worth noting that Regex can sometimes complicate things—if you want a simple match, avoid overloading it with unnecessary complexity. Just remember that syntax and the context are key!

I had similar issues before! When running Bash commands, especially involving lists or conditionals, you can encounter unexpected behavior after an error. The Bash environment can retain some state from the previous command. So when you run the valid command after an invalid one, it’s acting weirdly because of that state.

Those syntax errors can trip up Bash’s parsing, resulting in strange errors later even if the command seems correct. Try running them isolated one at a time to avoid this confusion.