Built-in domains

In addition to arrays, we need at least two built-in domains: Integer and String. Boolean can be skipped at a first stage. Indeed, we have booleans expressions and we can encode boolean values by integers.

Integer.

The built-in domain Integer needs to support the arithmetic operations appearing in ArithmeticExpression plus the print function with signature

print: (Integer) -> ()

String.

The built-in domain String needs to support creation (like in s: String := "Allcot") element access (like in AttributeCall) plus a concat and a print function with signatures

concat: (String, String) -> String
print: (String) -> ()

Note also that the grammar needs to be updated in order to have literal strings

RightValue	$\longmapsto$	LiteralString
LiteralString	$\longmapsto$	" string "