Lets take a broad look at it.
Well if you have access to source code and permission to edit it then yes why not.
Because wordpress is a content management system and not a programing language. Wordpress pages are also based on html, php, java etc.
Don't confuse wordpress with programming language its just an cms.
With wordpress you don't have to necessarily but you can edit the code given if you have permissions and access.
Have a good day.