刚才想实现vim自动插入文件头的功能，在 .vimrc 中用了如下代码

if [ &filetype == 'cpp' -o &filetype == 'c' ]
	call append(line("$"),"#define reg register")
	call append(line("$"),"#define EN puts(\"\")")
	call append(line("$"),"inline int read(){")
	call append(line("$"),"	register int x=0;register int y=1;")
	call append(line("$"),"	register char c=std::getchar();")
	call append(line("$"),"	while(c<'0'||c>'9'){if(c=='-') y=0;c=getchar();}")
	call append(line("$"),"	while(c>='0'&&c<='9'){x=x*10+(c^48);c=getchar();}")
	call append(line("$"),"	return y?x:-x;")
	call append(line("$"),"}")
	call append(line("$"),"int main(){")
	call append(line("$"),"	return 0;")
	call append(line("$"),"}")
	normal G
	normal kk
endif

然后报错

E121: 未定义的变量: o

话说 -o 我从网上查的是逻辑或，为什么会出现这个报错？