How to input a broken right arrow?

Dear all,

I wonder how to input a broken right arrow in TeXmacs? Something like --->, dashed or dotted. Thanks.


It is possible to use the unicode ⇢. However, I don’t know whether it is easy to make it extensible, and to add things above and below the arrow?

Perhaps the first step is to see how TeXmacs makes extensible “regular” (i.e. with solid shafts) arrows.

There might be a sizeable character for the normal right arrow. I am incapable to look into the internal implement of TeXmacs.