Restore for @a -> { } giving an exception.
Restore for @a -> { } giving an exception.

Fixes hang in dollar-underscore.t.

nunorc/rakudo,Gnouc/rakudo,awwaiid/rakudo,ab5tract/rakudo,ungrim97/rakudo,samcv/rakudo,softmoth/rakudo,paultcochrane/rakudo,sjn/rakudo,Gnouc/rakudo,usev6/rakudo,ungrim97/rakudo,cognominal/rakudo,nbrown/rakudo,cognominal/rakudo,rakudo/rakudo,b2gills/rakudo,samcv/rakudo,LLFourn/rakudo,skids/rakudo,samcv/rakudo,MasterDuke17/rakudo,ab5tract/rakudo,ugexe/rakudo,skids/rakudo,usev6/rakudo,tbrowder/rakudo,Gnouc/rakudo,labster/rakudo,tbrowder/rakudo,jonathanstowe/rakudo,tony-o/rakudo,dankogai/rakudo,salortiz/rakudo,salortiz/rakudo,ab5tract/rakudo,MasterDuke17/rakudo,sjn/rakudo,salortiz/rakudo,b2gills/rakudo,LLFourn/rakudo,tony-o/rakudo,labster/rakudo,tony-o/rakudo,awwaiid/rakudo,sjn/rakudo,azawawi/rakudo,lucasbuchala/rakudo,cygx/rakudo,samcv/rakudo,LLFourn/rakudo,paultcochrane/rakudo,ungrim97/rakudo,lucasbuchala/rakudo,nbrown/rakudo,tony-o/rakudo,ugexe/rakudo,salortiz/rakudo,rakudo/rakudo,awwaiid/rakudo,azawawi/rakudo,dankogai/rakudo,dankogai/rakudo,raydiak/rakudo,ab5tract/rakudo,ugexe/rakudo,paultcochrane/rakudo,nunorc/rakudo,jonathanstowe/rakudo,tony-o/rakudo,softmoth/rakudo,Gnouc/rakudo,jonathanstowe/rakudo,zostay/rakudo,labster/rakudo,lucasbuchala/rakudo,labster/rakudo,Gnouc/rakudo,raydiak/rakudo,rakudo/rakudo,zostay/rakudo,skids/rakudo,labster/rakudo,skids/rakudo,rakudo/rakudo,usev6/rakudo,nunorc/rakudo,MasterDuke17/rakudo,tbrowder/rakudo,dankogai/rakudo,softmoth/rakudo,LLFourn/rakudo,salortiz/rakudo,jonathanstowe/rakudo,azawawi/rakudo,nbrown/rakudo,cygx/rakudo,skids/rakudo,b2gills/rakudo,cygx/rakudo,labster/rakudo,salortiz/rakudo,usev6/rakudo,tony-o/rakudo,usev6/rakudo,raydiak/rakudo,nunorc/rakudo,awwaiid/rakudo,cognominal/rakudo,b2gills/rakudo,ungrim97/rakudo,azawawi/rakudo,b2gills/rakudo,softmoth/rakudo,softmoth/rakudo,nbrown/rakudo,MasterDuke17/rakudo,cognominal/rakudo,lucasbuchala/rakudo,cygx/rakudo,ab5tract/rakudo,tbrowder/rakudo,ungrim97/rakudo,awwaiid/rakudo,cognominal/rakudo,sjn/rakudo,ugexe/rakudo,sjn/rakudo,paultcochrane/rakudo,tbrowder/rakudo,jonathanstowe/rakudo,rakudo/rakudo,MasterDuke17/rakudo,rakudo/rakudo,ugexe/rakudo,nbrown/rakudo,zostay/rakudo,zostay/rakudo,paultcochrane/rakudo,cygx/rakudo,Gnouc/rakudo,raydiak/rakudo,MasterDuke17/rakudo,dankogai/rakudo,tbrowder/rakudo,lucasbuchala/rakudo,nbrown/rakudo,azawawi/rakudo,LLFourn/rakudo,samcv/rakudo