Dictionary keys with non-alphanumeric characters

Question

Given a dictionary:

let g:dict = {
    \ 'FOO/BAR': 'BAZ',
    \ 'FIZZ': 'BUZZ'
}

Vim is fine with this:

:echo g:dict.FIZZ

But chokes on this:

:echo g:dict.FOO/BAR

E716: Key not present in Dictionary: HCL/HCL_0127
E15: Invalid expression: g:dict.FOO/BAR

I've also tried escaping the forward slash as \/, which doesn't work. However, it has no problem with g:dict['FOO/BAR'].

Is there any way to access these entries using the dot syntax? Are there other characters I have to watch out for?

Answer 1

You cannot use the dot form in your case because your key has something other than a letter, number, underscore:

:help dict

Accessing entries

The normal way to access an entry is by putting the key in square brackets:

:let val = mydict["one"]
:let mydict["four"] = 4

You can add new entries to an existing Dictionary this way, unlike Lists.

For keys that consist entirely of letters, digits and underscore the following form can be used |expr-entry|:

:let val = mydict.one
:let mydict.four = 4