vim正则匹配问题

Question

1、在vi里想一次性替换以下内容，在线等...

'username' => 'hhhhdb',
'username' => 'dasfasfsaf',

将以上类似的内容替换成

'username' => 'admin',

自己匹配了半天也匹配不上，期待大神...

Answer 1

%s/\('username'\s\+=>\s\+'\)[^'"]\+'/\1admin'/g

Answer 2

%s/'username' => '\w\+'/'username' => 'admin'/ 

Answer 3

%s/'username' => '.*'/'username' => 'admin'