How to Convert a list of tuples into a Json string

I have a Erlang list of tuples as follows:

[  {{"a"},[2],[{3,"b"},{4,"c"}],[5,"d"],[1,1],{e},["f"]}  , 
   {{"g"},[3],[{6,"h"},{7,"i"}],[{8,"j"}],[1,1,1],{k},["L"]}  ]

I wanted this list of tuples in this form:

<<" [  {{"a"},[2],[{3,"b"},{4,"c"}],[5,"d"],[1,1],{e},["f"]} , 
       {{"g"},[3],[{6,"h"},{7,"i"}],[{8,"j"}],[1,1,1],{k},["L"]}] ">>

So I tried using JSON parsing libraries in erlang (both jiffy and jsx ) Here is what I did:

A=[  {{"a"},[2],[{3,"b"},{4,"c"}],[5,"d"],[1,1],{e},["f"]}  , 
       {{"g"},[3],[{6,"h"},{7,"i"}],[{8,"j"}],[1,1,1],{k},["L"]}  ],

B=erlang:iolist_to_binary(io_lib:write(A)),

jsx:encode(B).

and I get the following output(here I have changed the list to binary since jsx accepts binary):

 <<"[{{[97]},[2],[{3,[98]},{4,[99]}],[5,[100]],[1,1],{e},[[102]]},{{[103]},
 [3],[{6,[104]},{7,[105]}],[{8,[106]}],[1,1,1],{k},[[76]]}]">>

jiffy:encode(B) also gives the same output. Can anyone help me to get the output as :

<<" [  {{"a"},[2],[{3,"b"},{4,"c"}],[5,"d"],[1,1],{e},["f"]} , 
           {{"g"},[3],[{6,"h"},{7,"i"}],[{8,"j"}],[1,1,1],{k},["L"]}] ">>

instead of

<<"[{{[97]},[2],[{3,[98]},{4,[99]}],[5,[100]],[1,1],{e},[[102]]},{{[103]},
     [3],[{6,[104]},{7,[105]}],[{8,[106]}],[1,1,1],{k},[[76]]}]">>

Thank you in advance

Solution

Instead of io_lib:write(A), use io_lib:format("~p", [A]). It tries to guess which lists are actually meant to be strings. (In Erlang, strings are actually lists of integers. Try it: "A" == [65])

> A=[  {{"a"},[2],[{3,"b"},{4,"c"}],[5,"d"],[1,1],{e},["f"]}  ,
       {{"g"},[3],[{6,"h"},{7,"i"}],[{8,"j"}],[1,1,1],{k},["L"]}  ].
[{{"a"},[2],[{3,"b"},{4,"c"}],[5,"d"],[1,1],{e},["f"]},
 {{"g"},[3],[{6,"h"},{7,"i"}],[{8,"j"}],[1,1,1],{k},["L"]}]
> B = erlang:iolist_to_binary(io_lib:format("~p", [A])).
<<"[{{\"a\"},[2],[{3,\"b\"},{4,\"c\"}],[5,\"d\"],[1,1],{e},[\"f\"]},\n {{\"g\"},[3],[{6,\"h\"},{7,\"i\"}],[{8,\"j\"}],[1,1,1],{k},[\"L\"]}]">>

If you don't want to see the backslashes before the double quotes, you can print the string to standard output:

> io:format("~s\n", [B]).
[{{"a"},[2],[{3,"b"},{4,"c"}],[5,"d"],[1,1],{e},["f"]},
 {{"g"},[3],[{6,"h"},{7,"i"}],[{8,"j"}],[1,1,1],{k},["L"]}]