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Added a note to avoid issue #10

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Benoit Blanchon
2014-08-04 15:12:09 +02:00
parent 4bdbc6c1fc
commit 7246db7691
1 changed files with 27 additions and 0 deletions
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27
JsonGenerator/README.md
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@@ -101,6 +101,33 @@ or
JsonObject<8> nestedObject; JsonObject<8> nestedObject;
array.add(nestedObject); array.add(nestedObject);
> ##### CAUTION! Nested objects must be in memory
> Calling `add()` makes the `JsonArray` store a pointer to the nested object.
> This is designed to avoid memory duplication.
> But it can only work if the object is in memory when `printTo()` is executed.
> For instance, don't do this:
>
> void addNestedObject()
> {
> JsonObject<2> nestedObject;
> // ...
> array.add(nestedObject); // <- DON'T !!
>
> // array now contains a pointer to a local variable that will be
> // discarded as soon as the function exits
> }
>
> For the same reason, don't do this either:
>
> for( int i=0; i<100; i++)
> {
> JsonObject<2> nestedObject;
> // ...
> array.add(nestedObject); // <- DON'T !!
> }
> // array now contains 100 pointers to the same a local variable
> // that is out of the scope anyway
#### JSON Object #### JSON Object
You create a JSON object (ie hash-table/dictionary) with the following line: You create a JSON object (ie hash-table/dictionary) with the following line: