Cool.subst-mutate wrapper to handle coercion
Cool.subst-mutate wrapper to handle coercion

We can't simultaneously maintain coercion and 'rw' on the invocant
to Str.subst-mutate.  So we do the two-step shimmy instead.

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