Which characters are allowed in a bash alias

Question

I recently added

alias ..=\'cd ..\'
alias ...=\'cd ../..\'
alias ....=\'cd ../../..\'

to my bash_aliases file. Playing around with this, I not

Answer 1

According to the following environment variables names can only contain

uppercase letters, digits, and the '_' (underscore) from the characters defined in Portable Character Set and do not begin with a digit. Other characters may be permitted by an implementation; applications shall tolerate the presence of such names.

But variables are not really the same the same of alias names.

In practice a -(dash) should be added to the list because it is a defacto standard in debian(apt-get). In addition _~@#%^., all work and ><'"|=()backtick/?[]+!. don't. In addition you have to worry about $PATH and characters like :. It appears space and linebreaks could work if they are properly escaped or quoted like so "a b".