How to match a regex with backreference in Go? -


i need match regex uses backreferences (e.g. \1) in go code.

that's not easy because in go, official regexp package uses re2 engine, 1 have chosen not support backreferences (and other lesser-known features) there can guarantee of linear-time execution, therefore avoiding regex denial-of-service attacks. enabling backreferences support not option re2.

in code, there no risk of malicious exploitation attackers, , need backreferences.

what should do?

regular expressions great working regular grammars, if grammar isn't regular (i.e. requires back-references , stuff that) should switch better tool. there lot of tools available parsing context-free grammars, including yacc shipped go distribution default. alternatively, can write own parser. recursive descent parsers can written hand example.

i think regular expressions overused in scripting languages (like perl, python, ruby, ...) because c/asm powered implementation more optimized languages itself, go isn't such language. regular expressions quite slow , not suited problem @ all.


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