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/** @page tut_bson_build Building BSON objects
*
* Our first task will be to build a BSON document, which we can later
* insert into MongoDB. For this example, we want something more
* complex than a simple "Hello World"-style object, so we can
* showcase all the interesting functions of the BSON API.
*
* Lets build a document that would look like this, if we were writing
* JSON:
* @verbinclude tut_bson_build.json
*
* @dontinclude tut_bson_build.c
*
* First we start by including the main libmongo-client header. It's
* convenient to include the whole lot instead of including the used
* headers one by one, unless one's embedding only parts of the
* library.
* @until mongo.h
*
* @until {
*
* We'll be building the same BSON object in various different ways,
* so we declare a few more variables than we'd normally need.
* @until pages
*
* Next, we create the two pages:
* @until bson_finish (page2)
*
* Then we construct the "pages" array. Do note how we set the key to
* "1" and "2", and how pages is just a document! This is because in
* BSON, an array is a document that has a special type, and where
* keys are numbers.
* @until bson_finish (pages)
*
* Finally, now that we have all the subdocuments ready, we build up
* our main object:
* @until bson_finish (b_new)
*
* And that's about it! But surely, there is an easier way to do
* this... And indeed, there is, using bson_build():
* @until bson_finish (b_builder)
*
* Much cleaner, but still, we had to create the pages array in three
* steps beforehand. Couldn't we do it in one gigantic function call
* instead?
* @until bson_finish (b_builder_full)
*
* Wonderful! We have three BSON objects created now, in three
* different ways! But are they the same? That's really easy to figure
* out. As a quick check, we can compare their sizes: if they do not
* match, we can bail out fast:
* @until }
*
* Or, we can do a more expensive comparsion, and compare the data:
* @until }
*
* And now that we are done, we free up the resources we allocated.
* @until bson_free (page1)
*
*
* @until }
*/
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