continent-scopes2.taq

$ java -jar taq.jar continent-scopes2

Running query asia_megacities in global scope 
megacities(Megacity=Tokyo, Country=Japan, Continent=Asia)
megacities(Megacity=Delhi, Country=India, Continent=Asia)
megacities(Megacity=Seoul, Country=South Korea, Continent=Asia)
megacities(Megacity=Shanghai, Country=China, Continent=Asia)
megacities(Megacity=Mumbai, Country=India, Continent=Asia)
megacities(Megacity=Beijing, Country=China, Continent=Asia)
megacities(Megacity=Jakarta, Country=Indonesia, Continent=Asia)
megacities(Megacity=Karachi, Country=Pakistan, Continent=Asia)
megacities(Megacity=Osaka, Country=Japan, Continent=Asia)
megacities(Megacity=Manila, Country=Philippines, Continent=Asia)
megacities(Megacity=Dhaka, Country=Bangladesh, Continent=Asia)
megacities(Megacity=Kolkata, Country=India, Continent=Asia)
megacities(Megacity=Bangkok, Country=Thailand, Continent=Asia)
megacities(Megacity=Tehran, Country=Iran, Continent=Asia)
megacities(Megacity=Guangzhou, Country=China, Continent=Asia)
megacities(Megacity=Shenzhen, Country=China, Continent=Asia)
megacities(Megacity=Lahore, Country=Pakistan, Continent=Asia)
megacities(Megacity=Tianjin, Country=China, Continent=Asia)
megacities(Megacity=Bengaluru, Country=India, Continent=Asia)
megacities(Megacity=Chennai, Country=India, Continent=Asia)
megacities(Megacity=Hyderabad, Country=India, Continent=Asia)

Running query euro_megacities in global scope 
megacities(Megacity=Moscow, Country=Russia, Continent=Europe)
megacities(Megacity=London, Country=United Kingdom, Continent=Europe)
megacities(Megacity=Istanbul, Country=Turkey, Continent=Europe)
megacities(Megacity=Rhine-Ruhr, Country=Germany, Continent=Europe)
megacities(Megacity=Paris, Country=France, Continent=Europe)

Description

continent-scopes2.taq illustrates address identifiers where an ‘@’ symbol is used to signify the scope part of the identifier. The only change from the original program is to use addresses in the query declarations

query<axiom> euro_megacities (mega_city@ : @Europe.megacities)

The “mega_city@” identifier is an artifact address that references an axiom source in the global scope. In this case, the name of the scope can be omitted. The full address is “mega_city@global”.

The “@Europe.megacities” identifier is a template address signified by having the “@’ symbol at the start of the identifier. A template address is always a 2-part name, even for the global scope.

Whether to use addresses in place of plain identifiers is almost without exception a matter of preference. Despite the low occurrence of addresses in the examples, it is recommended to use addresses to reference artifacts that are declared other than the immidiate vicinity.