refactor Dictionary to support an empty singleton
refactor Dictionary to support an empty singleton

gmilos/swift,ben-ng/swift,shajrawi/swift,atrick/swift,jmgc/swift,gribozavr/swift,deyton/swift,lorentey/swift,stephentyrone/swift,tkremenek/swift,shajrawi/swift,parkera/swift,practicalswift/swift,gmilos/swift,ben-ng/swift,shahmishal/swift,jtbandes/swift,shahmishal/swift,allevato/swift,huonw/swift,roambotics/swift,glessard/swift,felix91gr/swift,therealbnut/swift,calebd/swift,tjw/swift,Jnosh/swift,swiftix/swift,amraboelela/swift,natecook1000/swift,ahoppen/swift,parkera/swift,danielmartin/swift,swiftix/swift,practicalswift/swift,austinzheng/swift,swiftix/swift,frootloops/swift,harlanhaskins/swift,bitjammer/swift,natecook1000/swift,uasys/swift,benlangmuir/swift,atrick/swift,jckarter/swift,jopamer/swift,felix91gr/swift,frootloops/swift,gregomni/swift,kstaring/swift,jmgc/swift,felix91gr/swift,deyton/swift,benlangmuir/swift,nathawes/swift,lorentey/swift,tinysun212/swift-windows,gottesmm/swift,apple/swift,OscarSwanros/swift,milseman/swift,glessard/swift,djwbrown/swift,nathawes/swift,tinysun212/swift-windows,parkera/swift,amraboelela/swift,alblue/swift,uasys/swift,brentdax/swift,airspeedswift/swift,codestergit/swift,jmgc/swift,CodaFi/swift,jopamer/swift,karwa/swift,djwbrown/swift,arvedviehweger/swift,shajrawi/swift,danielmartin/swift,felix91gr/swift,hooman/swift,calebd/swift,austinzheng/swift,roambotics/swift,glessard/swift,gribozavr/swift,karwa/swift,JaSpa/swift,OscarSwanros/swift,CodaFi/swift,amraboelela/swift,calebd/swift,rudkx/swift,jckarter/swift,milseman/swift,gmilos/swift,brentdax/swift,tkremenek/swift,milseman/swift,natecook1000/swift,glessard/swift,hughbe/swift,danielmartin/swift,brentdax/swift,alblue/swift,brentdax/swift,apple/swift,huonw/swift,tjw/swift,deyton/swift,JGiola/swift,return/swift,bitjammer/swift,xedin/swift,alblue/swift,devincoughlin/swift,practicalswift/swift,airspeedswift/swift,codestergit/swift,gottesmm/swift,frootloops/swift,jtbandes/swift,xedin/swift,CodaFi/swift,hooman/swift,OscarSwanros/swift,kstaring/swift,jopamer/swift,stephentyrone/swift,nathawes/swift,swiftix/swift,huonw/swift,aschwaighofer/swift,gribozavr/swift,nathawes/swift,austinzheng/swift,tjw/swift,xwu/swift,benlangmuir/swift,practicalswift/swift,hughbe/swift,parkera/swift,xedin/swift,devincoughlin/swift,lorentey/swift,OscarSwanros/swift,codestergit/swift,xwu/swift,Jnosh/swift,tardieu/swift,parkera/swift,therealbnut/swift,ben-ng/swift,Jnosh/swift,karwa/swift,stephentyrone/swift,shahmishal/swift,ahoppen/swift,kstaring/swift,uasys/swift,return/swift,JGiola/swift,huonw/swift,lorentey/swift,austinzheng/swift,jtbandes/swift,OscarSwanros/swift,ahoppen/swift,milseman/swift,airspeedswift/swift,swiftix/swift,arvedviehweger/swift,parkera/swift,practicalswift/swift,hughbe/swift,parkera/swift,JaSpa/swift,zisko/swift,OscarSwanros/swift,frootloops/swift,alblue/swift,shajrawi/swift,gregomni/swift,shahmishal/swift,aschwaighofer/swift,jckarter/swift,djwbrown/swift,jckarter/swift,arvedviehweger/swift,zisko/swift,brentdax/swift,manavgabhawala/swift,kstaring/swift,gottesmm/swift,gregomni/swift,sschiau/swift,xedin/swift,practicalswift/swift,felix91gr/swift,tkremenek/swift,benlangmuir/swift,hughbe/swift,natecook1000/swift,calebd/swift,karwa/swift,devincoughlin/swift,JGiola/swift,xwu/swift,kstaring/swift,hooman/swift,therealbnut/swift,lorentey/swift,uasys/swift,allevato/swift,xwu/swift,OscarSwanros/swift,gribozavr/swift,shajrawi/swift,Jnosh/swift,tkremenek/swift,return/swift,apple/swift,uasys/swift,aschwaighofer/swift,airspeedswift/swift,amraboelela/swift,gribozavr/swift,milseman/swift,gmilos/swift,karwa/swift,codestergit/swift,atrick/swift,austinzheng/swift,nathawes/swift,roambotics/swift,ben-ng/swift,shajrawi/swift,harlanhaskins/swift,calebd/swift,shajrawi/swift,zisko/swift,shajrawi/swift,amraboelela/swift,roambotics/swift,aschwaighofer/swift,alblue/swift,tinysun212/swift-windows,gottesmm/swift,devincoughlin/swift,jmgc/swift,jtbandes/swift,gmilos/swift,ahoppen/swift,Jnosh/swift,therealbnut/swift,bitjammer/swift,gregomni/swift,devincoughlin/swift,parkera/swift,kstaring/swift,milseman/swift,hooman/swift,atrick/swift,ben-ng/swift,nathawes/swift,CodaFi/swift,roambotics/swift,harlanhaskins/swift,atrick/swift,hughbe/swift,zisko/swift,manavgabhawala/swift,jopamer/swift,hughbe/swift,stephentyrone/swift,natecook1000/swift,sschiau/swift,tjw/swift,sschiau/swift,therealbnut/swift,Jnosh/swift,arvedviehweger/swift,xedin/swift,JGiola/swift,tinysun212/swift-windows,jmgc/swift,atrick/swift,JGiola/swift,tardieu/swift,hooman/swift,jtbandes/swift,stephentyrone/swift,natecook1000/swift,brentdax/swift,nathawes/swift,tardieu/swift,djwbrown/swift,shahmishal/swift,sschiau/swift,JaSpa/swift,swiftix/swift,Jnosh/swift,djwbrown/swift,felix91gr/swift,deyton/swift,danielmartin/swift,jckarter/swift,CodaFi/swift,frootloops/swift,benlangmuir/swift,xedin/swift,gribozavr/swift,devincoughlin/swift,jopamer/swift,tkremenek/swift,xedin/swift,stephentyrone/swift,xwu/swift,amraboelela/swift,glessard/swift,harlanhaskins/swift,xwu/swift,practicalswift/swift,huonw/swift,zisko/swift,deyton/swi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