Q: is it possible to define some global variables?

[yurenchen000]

I use swagger ui before. I found oax today, it's awsome!!

I always want to define some global variable, so I can use them at anyway in openapi.yml.

like the variable used in bash or javascript string:

var1='abc123'
str1=`hello ${var1}`

original openapi spec seem not support this, extensions or some hack can do it easily?