Clarify the use of parameter indices and `self`.
Clarify the use of parameter indices and `self`.

atrick/swift,glessard/swift,hooman/swift,JGiola/swift,ahoppen/swift,jckarter/swift,roambotics/swift,roambotics/swift,ahoppen/swift,harlanhaskins/swift,parkera/swift,glessard/swift,gribozavr/swift,airspeedswift/swift,jmgc/swift,nathawes/swift,CodaFi/swift,jmgc/swift,parkera/swift,xwu/swift,parkera/swift,aschwaighofer/swift,xwu/swift,JGiola/swift,gribozavr/swift,rudkx/swift,harlanhaskins/swift,airspeedswift/swift,benlangmuir/swift,gribozavr/swift,gregomni/swift,aschwaighofer/swift,apple/swift,xwu/swift,allevato/swift,parkera/swift,jckarter/swift,harlanhaskins/swift,CodaFi/swift,roambotics/swift,glessard/swift,harlanhaskins/swift,tkremenek/swift,atrick/swift,allevato/swift,ahoppen/swift,parkera/swift,apple/swift,allevato/swift,atrick/swift,aschwaighofer/swift,jckarter/swift,gregomni/swift,gregomni/swift,benlangmuir/swift,allevato/swift,tkremenek/swift,jmgc/swift,jckarter/swift,CodaFi/swift,stephentyrone/swift,CodaFi/swift,CodaFi/swift,nathawes/swift,harlanhaskins/swift,glessard/swift,rudkx/swift,jmgc/swift,gribozavr/swift,gribozavr/swift,aschwaighofer/swift,stephentyrone/swift,roambotics/swift,JGiola/swift,xwu/swift,hooman/swift,harlanhaskins/swift,gregomni/swift,rudkx/swift,aschwaighofer/swift,jckarter/swift,CodaFi/swift,ahoppen/swift,airspeedswift/swift,parkera/swift,stephentyrone/swift,ahoppen/swift,hooman/swift,jckarter/swift,aschwaighofer/swift,rudkx/swift,CodaFi/swift,tkremenek/swift,hooman/swift,allevato/swift,gribozavr/swift,JGiola/swift,nathawes/swift,gregomni/swift,stephentyrone/swift,allevato/swift,jmgc/swift,nathawes/swift,hooman/swift,airspeedswift/swift,xwu/swift,JGiola/swift,hooman/swift,airspeedswift/swift,glessard/swift,roambotics/swift,roambotics/swift,nathawes/swift,JGiola/swift,harlanhaskins/swift,benlangmuir/swift,nathawes/swift,tkremenek/swift,ahoppen/swift,atrick/swift,benlangmuir/swift,stephentyrone/swift,xwu/swift,parkera/swift,allevato/swift,tkremenek/swift,gribozavr/swift,stephentyrone/swift,benlangmuir/swift,apple/swift,jmgc/swift,apple/swift,benlangmuir/swift,nathawes/swift,rudkx/swift,atrick/swift,stephentyrone/swift,gribozavr/swift,hooman/swift,jmgc/swift,glessard/swift,gregomni/swift,apple/swift,airspeedswift/swift,tkremenek/swift,apple/swift,tkremenek/swift,jckarter/swift,parkera/swift,rudkx/swift,aschwaighofer/swift,xwu/swift,atrick/swift,airspeedswift/swift