regex: how to replace "\["?

Question

I have this sample line in the buffer:

export PS1="\[${Cyan}\]$(((SHLVL>1)) && echo "${SHLVL}\[${IBlack}\].")\[${IGreen}\]\u\[${IBlack}\]@\[${Purple}\]\h\[${IYellow}\] \w \$ \[${Color_Off}\]"

and i want to delete all \[ so while the cursor is on the line i write :s/\\[//g and get the error

E486: Pattern not found: \\[//g

What do i do wrong? Somehow vim thinks that //g is part of the pattern?

When i search with /\\[ i get proper results.

Answer 1

I found the reason: [ is special character so vim treats next characters as part of the set ([...]) although it doesn't have the closing bracket. The proper replace should be:

:s/\\\[//g

(One backslash more)

Answer 2

The error gives it away: Vim interprets the whole \\[//g as the pattern. It doesn't recognize the / separator because the [ starts an (unclosed) collection. You either need to escape (via another backslash: :s/\\\[//g, or use very nomagic mode via \V: :s/\V\\[//g.

Answer 3

If this would be slash, you could use another delimiter, however backslash (\) is metacharacter which escapes any separator, so there is no way to omit two backslashes for backslash it-self. The same with [.

However using different delimiter can still improve the readability:

:s,\\\[,,g
:s@\\\[@@g
:s#\\\[##g
:s|\\\[||g

I've tried to test with <Bslash>, but it seems substitute doesn't accept it.