erlang - How to get binary data into integer on mapreduce in riak -


i working on riak-erlang client ,

i have done following...

3> mapf = fun(obj,_,_) -> [riak_object:get_value(obj)] end. #fun<erl_eval.18.82930912> 4>  4>  {ok, [{0,[r]}]} = riakc_pb_socket:mapred(pid,<<"tst">>, [{map{qfun,mapf},none,true}]).     ** exception error: no match of right hand side value {ok,[{0,[<<"2">>,<<"4">>,<<"6">>,<<"3">>,<<"5">>,<<"1">>]}]}

how solve issue

and how solve these kind of issue 

{ok, [{0,[s]}]} = riakc_pb_socket:mapred(pid,<<"test">>,[{map,  {qfun,maps},none,true}]).    ** exception error: no match of right hand side value {ok,[{0,                                                         [<<"{\"age\": 24, \"name\": \"krishna\"}">>,                                                          <<"{\"age\": 29, \"name\": \"sharat\"}">>,                                                          <<"{\"age\": 27, \"name\": \"anil\"}">>,                                                          <<"{\"age\": 28, \"name\": \"kumar\"}">>,                                                          <<"{\"age\": 24, \"name\": \"gopi\"}">>,                                                          <<"{\"age\": 25, \"name\": \"ramesh\"}">>]}]}

if want age , age even. how write map function.

you have pattern matching issues. try both times match list using [r] = [<<data…>>,…].

[r] matches 1-element list, element being r.
need remove brackets match whole data structure, so: {ok, [{0,r}].


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