when trying to search for open and closed brackets, the standard regex : /[\[|\]] does not find any results where as if you flip the brackets, /[\]|\[]

In version 2.2.6

testing on text
[xxxx]

commands:

s/[\[|\]]//g  -- should remove the start and end brackets - but doesn't

s/[\]|\[]//g -- where as this works

To confirm both commands work properly in VIM 7.2