Topic on Help talk:CirrusSearch

Why is '#' a regex special character?

3
AlanM1 (talkcontribs)
PerfektesChaos (talkcontribs)

elastic.co suggests that this is used to introduce a comment, especially in a multiline environment. It has no syntactic meaning like any other reserved character.

In our environment it breaks any RegExp, apparently with no result ever if not escaped.

197.235.216.151 (talkcontribs)

Simply because cirrussearch uses elasticsearch, which in turn uses lucene search, and it defines its own regex that interprets that as an "empty language":https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-regexp-query.html .

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