Problem

Due to the simplified regular expression for matching used in Postgres CPS-Core might have problems with some special characters in certain situations

e.g.

Referencing a list key string-value that contains at least one '/':

 //categories[@code='with/slash']/book[@title='search']

Referencing  a list key string-value that contains '@[': 

//categories[@code='strange code with  @[']/book[@title='search']

The result of these limitations will be that any records where the key-field of an index contains a slash or the combination of @[ these records will be ignored when the user uses an xpath like '//categories'

Although the occurrence of a slash in the index fields is not unlikely it probably will not happen for any models used in Istanbul release.

Suggested Solution

1. For now document these limitations in  docs/cps-path.rst
2. Create (low priority) Jira to address this issue as needed or when time allows