Erlang binary pattern matching fails -

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why issue badmatch error? can't figure out why fail:

<<ipaddr, ":*:*">> = <<"2a01:e34:ee8b:c080:a542:ffaf:*:*">>.

pattern matching of binary proceeds left-to-right match ipaddr first before tries following segment. there no back-tracking until there match. default typed variable ipaddr matches 1 byte. see bit syntax expressions , bit syntax proper description , more examples.

as alternative using pattern matching here might consider using binary module. there 2 functions useful you: binary:match/2/3 , binary:split/2/3. these search may better fit problem.

as last alternative try using regular expressions , re module.


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