解决vim中右健无法复制

发现vim中,鼠标右健无法复制. 在配置文件(./vimrc)中发现,有这样一段话:
 44 " In many terminal emulators the mouse works just fine, thus enable it.
 45 if has('mouse')
 46   set mouse=a
 47 endif

这里不得不说到vi的三种模式:命令模式,插入模式,可视模式.鼠标可以启动于各种模式中:
The mouse can be enabled for different modes:
                n       Normal mode
                v       Visual mode
                i       Insert mode
                c       Command-line mode
                h       all previous modes when editing a help file
                a       all previous modes
                r       for |hit-enter| and |more-prompt| prompt
Normally you would enable the mouse in all four modes with:
                :set mouse=a
When the mouse is not enabled, the GUI will still use the mouse for
modeless selection.  This doesn't move the text cursor.

所以配置文件中的set mouse=a启动了所有模式,这样就屏蔽了鼠标右健功能.解决方法是把模式设置
为空值    :set mouse=