Hello World
class HELLO_WORLD is main is #OUT+"Hello World\n"; end; end;A few remarks:
- Class names are ALL CAPS; this is not only a convention but is enforced by the compiler.
- The method called
mainis the entry point for execution. It may belong to any class, but if this is different fromMAIN, it must be specified as a compiler option. #is the constructor symbol, calling methodcreateof the corresponding class; here it is used for instantiating theOUTclass, which is actually stdout.- The
+operator has been overloaded here to stand for stream append. - Operators such as
+are syntactic sugar for conventionally named method calls:a + bstands fora.plus(b). The usual arithmetic precedence conventions are used to resolve the calling order of methods in complex formulae. - The program layout allows for pre- and post-conditions (not shown here), showing Sather's Eiffel lineage.
Read more about this topic: Sather
Famous quotes containing the word world:
“Our policy is directed not against any country or doctrine, but against hunger, poverty, desperation and chaos. Its purpose should be the revival of a working economy in the world so as to permit the emergence of political and social conditions in which free institutions can exist.”
—George Marshall (18801959)
“It is not contrary to reason to prefer the destruction of the whole world to the scratching of my finger. It is not contrary to reason for me to choose my total ruin, to prevent the least uneasiness of an Indian, or person wholly unknown to me. It is as little contrary to reason to prefer even my own acknowledged lesser good to my greater, and have a more ardent affection for the former than the latter.”
—David Hume (17111776)