Unknown C++ braces syntaxis -

this question has answer here:

• what purpose of anonymous { } blocks in c style languages? 16 answers

look @ snippet:

void sample_compositor::createeffects(void) {     ogre::compositorptr comp3 = ogre::compositormanager::getsingleton().create("motion blur", ogre::resourcegroupmanager::default_resource_group_name);     {         {             ogre::compositiontargetpass *tp = t->getoutputtargetpass();             tp->setinputmode(ogre::compositiontargetpass::im_none);             {                 ogre::compositionpass *pass = tp->createpass();                 pass->settype(ogre::compositionpass::pt_renderquad);                 pass->setmaterialname("ogre/compositor/motionblur");                 pass->setinput(0, "sum");             }         }     } } 

if code legit, how these blocks work?

they blocks introduce scope, , hide contents. valid.