Add defined? keyword support for x-strings
Add defined? keyword support for x-strings

merongivian/opal,bbatsov/opal,c42engineering/opal,charliesome/opal,Mogztter/opal,charliesome/opal,iliabylich/opal,kachick/opal,fazibear/opal,Ajedi32/opal,Flikofbluelight747/opal,merongivian/opal,castwide/opal,gabrielrios/opal,Mogztter/opal,gabrielrios/opal,merongivian/opal,kachick/opal,catprintlabs/opal,bbatsov/opal,c42engineering/opal,gausie/opal,suyesh/opal,jgaskins/opal,domgetter/opal,fazibear/opal,opal/opal,kachick/opal,wied03/opal,castwide/opal,Flikofbluelight747/opal,Mogztter/opal,Flikofbluelight747/opal,domgetter/opal,Mogztter/opal,gausie/opal,wied03/opal,gabrielrios/opal,castwide/opal,c42engineering/opal,suyesh/opal,opal/opal,jgaskins/opal,gausie/opal,jannishuebl/opal,opal/opal,catprintlabs/opal,wied03/opal,bbatsov/opal,iliabylich/opal,kachick/opal,jgaskins/opal,jannishuebl/opal,Ajedi32/opal,opal/opal,suyesh/opal,iliabylich/opal,Ajedi32/opal,jannishuebl/opal,fazibear/opal,catprintlabs/opal