Unexpected namespace assignment for PCRE containing colon

# Grammar
```
%token  foobar5            ns:bar   -> destinationNS
```

# Results

* grammar is resolved to
  + namespace `foobar5            ns`
  + token `bar`
  + PCRE `-> destinationNS`
  + target ø (empty)
* see https://regex101.com/r/B8cdSR/1

