```
$ dmd -of ~/READ[TAB] => TAB completion works
$ dmd -of=~/READ[TAB] => no TAB completion because preceeded by `=`
```

how would I customize the separators after which TAB completion operates?
Ideally something analog to $WORDCHARS (eg: $TAB_COMPLETION_CHARS, eg:
```
export TAB_COMPLETION_CHARS=":= "
```

Please let me know if anything is unclear