The Fortress Language Specification - CiteSeerX

Negating the literal 0 produces a special negative-zero object, which refuses to participate in compile-time constant
arithmetic (discussed in Section 13.27). It has type NegativeZero. The main thing it is good for is coercion to a
floating-point number (discussed in Chapter 17). (Negating any other zero-valued expression simply produces zero.)
13.2 Identifier References
Syntax:
Expr ::= DottedName[StaticArgList ]
| self
DottedName ::= DottedId
| opr Op
A name that is not an operator appearing in an expression context is called an identifier reference. It evaluates to the
value of the name in the enclosing scope in the value namespace. The type of an identifier reference is the declared
type of the name. See Chapter 7 for a discussion of names. An identifier reference performs a memory read operation.
Note in particular that if a name is not in scope, it is a static error (as described in Section 7.2).
An identifier reference which denotes a polymorphic function may include explicit type arguments (described in
Chapter 12) but most identifier references do not include them; the type arguments are statically inferred from the
context of the method invocation (as described in Chapter 20). For example, identityString is an identifier reference
with an explicit type argument where the function identity is defined as follows:
identityT(x :T) :T = x
The special name self is declared as a parameter of a method. When the method is invocated, its receiver is bound
to the self parameter; the value of self is the receiver. The type of self is the type of the trait or object being
declared by the innermost enclosing trait or object declaration or object expression. See Section 9.2 for details about
self parameters.
13.3 Dotted Field Accesses
Syntax:
Expr ::= Expr . Id
An expression consisting of a single subexpression (called the receiver expression), followed by ‘.’, followed by a
name, not immediately followed by a parenthesis, is a field access. If the receiver expression denotes an object (called
the receiver), the field access is evaluated to a call to a getter mapped from that name by the receiver. The type of the
field access is the return type of its getter. The static type of the receiver indicates whether a getter mapped from that
name is provided by the denoted object. If a getter is not provided, it is a static error. See Section 9.2 for a discussion
of getters.
13.4 Dotted Method Invocations
Syntax:
Expr ::= Expr . Id[StaticArgList ]([ExprList])
| TraitType.coercion[StaticArgList ](Expr)
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