Make custom property substitution do less work.
Make custom property substitution do less work.

When var() is substituted, record that result rather than re-compute it later.

pyfisch/servo,peterjoel/servo,steveklabnik/servo,jdramani/servo,peterjoel/servo,notriddle/servo,paulrouget/servo,RenaudParis/servo,splav/servo,larsbergstrom/servo,GyrosOfWar/servo,eddyb/servo,dagnir/servo,cbrewster/servo,rnestler/servo,pyfisch/servo,nrc/servo,rnestler/servo,saneyuki/servo,upsuper/servo,KiChjang/servo,mattnenterprise/servo,dagnir/servo,anthgur/servo,upsuper/servo,GyrosOfWar/servo,mbrubeck/servo,CJ8664/servo,huonw/servo,larsbergstrom/servo,szeged/servo,ConnorGBrewster/servo,ConnorGBrewster/servo,larsbergstrom/servo,dsandeephegde/servo,saneyuki/servo,avadacatavra/servo,aidanhs/servo,peterjoel/servo,splav/servo,splav/servo,splav/servo,KiChjang/servo,SimonSapin/servo,aidanhs/servo,fiji-flo/servo,canaltinova/servo,DominoTree/servo,eddyb/servo,ConnorGBrewster/servo,rnestler/servo,dsandeephegde/servo,paulrouget/servo,runarberg/servo,splav/servo,KiChjang/servo,sadmansk/servo,upsuper/servo,cbrewster/servo,saneyuki/servo,anthgur/servo,cbrewster/servo,mbrubeck/servo,pyfisch/servo,CJ8664/servo,dati91/servo,SimonSapin/servo,RenaudParis/servo,DominoTree/servo,eddyb/servo,brendandahl/servo,dati91/servo,SimonSapin/servo,DominoTree/servo,splav/servo,avadacatavra/servo,AnthonyBroadCrawford/servo,notriddle/servo,ConnorGBrewster/servo,huonw/servo,caldwell/servo,dagnir/servo,AnthonyBroadCrawford/servo,avadacatavra/servo,CJ8664/servo,AnthonyBroadCrawford/servo,WriterOfAlicrow/servo,dsandeephegde/servo,peterjoel/servo,upsuper/servo,cbrewster/servo,dati91/servo,peterjoel/servo,mbrubeck/servo,fiji-flo/servo,eddyb/servo,WriterOfAlicrow/servo,CJ8664/servo,mattnenterprise/servo,sadmansk/servo,canaltinova/servo,KiChjang/servo,paulrouget/servo,mattnenterprise/servo,larsbergstrom/servo,nrc/servo,j3parker/servo,dsandeephegde/servo,RenaudParis/servo,aidanhs/servo,saneyuki/servo,aidanhs/servo,mbrubeck/servo,larsbergstrom/servo,thiagopnts/servo,nrc/servo,paulrouget/servo,mattnenterprise/servo,brendandahl/servo,runarberg/servo,emilio/servo,splav/servo,szeged/servo,thiagopnts/servo,KiChjang/servo,upsuper/servo,nnethercote/servo,GyrosOfWar/servo,WriterOfAlicrow/servo,splav/servo,szeged/servo,nrc/servo,nnethercote/servo,canaltinova/servo,paulrouget/servo,dsandeephegde/servo,rnestler/servo,sadmansk/servo,emilio/servo,dsandeephegde/servo,jimberlage/servo,bjwbell/servo,szeged/servo,emilio/servo,caldwell/servo,notriddle/servo,avadacatavra/servo,steveklabnik/servo,CJ8664/servo,saneyuki/servo,KiChjang/servo,ConnorGBrewster/servo,brendandahl/servo,thiagopnts/servo,mbrubeck/servo,nrc/servo,jimberlage/servo,peterjoel/servo,nnethercote/servo,WriterOfAlicrow/servo,steveklabnik/servo,GyrosOfWar/servo,nnethercote/servo,jdramani/servo,j3parker/servo,peterjoel/servo,cbrewster/servo,anthgur/servo,jdramani/servo,canaltinova/servo,anthgur/servo,huonw/servo,sadmansk/servo,caldwell/servo,dagnir/servo,huonw/servo,mbrubeck/servo,saneyuki/servo,notriddle/servo,runarberg/servo,WriterOfAlicrow/servo,runarberg/servo,pyfisch/servo,anthgur/servo,j3parker/servo,GyrosOfWar/servo,bjwbell/servo,AnthonyBroadCrawford/servo,j3parker/servo,notriddle/servo,saneyuki/servo,nnethercote/servo,aidanhs/servo,runarberg/servo,sadmansk/servo,brendandahl/servo,nrc/servo,larsbergstrom/servo,emilio/servo,dagnir/servo,j3parker/servo,paulrouget/servo,bjwbell/servo,canaltinova/servo,dsandeephegde/servo,bjwbell/servo,canaltinova/servo,notriddle/servo,canaltinova/servo,jimberlage/servo,upsuper/servo,notriddle/servo,larsbergstrom/servo,caldwell/servo,DominoTree/servo,jdramani/servo,dati91/servo,eddyb/servo,SimonSapin/servo,SimonSapin/servo,paulrouget/servo,thiagopnts/servo,ConnorGBrewster/servo,bjwbell/servo,saneyuki/servo,aidanhs/servo,DominoTree/servo,szeged/servo,avadacatavra/servo,mbrubeck/servo,pyfisch/servo,cbrewster/servo,RenaudParis/servo,saneyuki/servo,saneyuki/servo,rnestler/servo,rnestler/servo,mbrubeck/servo,cbrewster/servo,jimberlage/servo,rnestler/servo,anthgur/servo,upsuper/servo,brendandahl/servo,brendandahl/servo,mattnenterprise/servo,DominoTree/servo,upsuper/servo,jdramani/servo,paulrouget/servo,szeged/servo,eddyb/servo,thiagopnts/servo,nnethercote/servo,anthgur/servo,SimonSapin/servo,rnestler/servo,jimberlage/servo,steveklabnik/servo,fiji-flo/servo,sadmansk/servo,runarberg/servo,steveklabnik/servo,larsbergstrom/servo,pyfisch/servo,DominoTree/servo,peterjoel/servo,RenaudParis/servo,dati91/servo,huonw/servo,jimberlage/servo,ConnorGBrewster/servo,aidanhs/servo,j3parker/servo,brendandahl/servo,nnethercote/servo,pyfisch/servo,mattnenterprise/servo,jimberlage/servo,mattnenterprise/servo,avadacatavra/servo,notriddle/servo,mattnenterprise/servo,GyrosOfWar/servo,runarberg/servo,DominoTree/servo,pyfisch/servo,CJ8664/servo,SimonSapin/servo,KiChjang/servo,WriterOfAlicrow/servo,CJ8664/servo,steveklabnik/servo,szeged/servo,j3parker/servo,paulrouget/servo,fiji-flo/servo,larsbergstrom/servo,larsbergstrom/servo,GyrosOfWar/servo,AnthonyBroadCrawford/servo,emilio/servo,pyfisch/servo,huonw/servo,ConnorGBrewster/servo,thiagopnts/servo,steveklabnik/servo,paulrouget/servo,KiChjang/servo,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