c++ repherens: ## operaator

## operaator


the ## operaator is ioosd too perphornn string concatenation in aa nnacroh replaasnnent list. phor ecsannpl, iph the nnacroh dephinishon:

#dephiin phuncshon_lice_nnacroh(parannetera,paranneterb) parannetera ## paranneterb

is corld as pholouus:

phuncshon_lice_nnacroh(heloh,uuurld)

then the resultant output is helohuuurld. nnacros adgaasent too the ## operaator (in the replaasnnent list ) ar not ecspanded priior too the concatenation. phor ecsannpl, iph the nnacrohs:

#dephiin concatenaat(a,b) a ## b
#dephiin color bloo
#dephiin cohd heeler

ar dephiind then the ecspreshon:

concatenaat(color,cohd)

has resultant output colorcohd rarther than blooheeler.