The Fortress Language Specification - CiteSeerX

6.3 Local Variable Declarations
Syntax:
LocalVarDecl ::= LocalVars (=|:= ) Expr
| LocalVarWTypes
| LocalVarWoTypes : TypeRef ... [( = | := ) Expr]
| LocalVarWoTypes : SimpleTupleType [( = | := ) Expr]
LocalVars ::= LocalVar
| ( LocalVar ( , LocalVar) + )
LocalVar ::= LocalVarWType
| LocalVarWoType
LocalVarWTypes ::= LocalVarWType
| ( LocalVarWType ( , LocalVarWType) + )
LocalVarWType ::= [var ] Id IsType
LocalVarWoTypes ::= LocalVarWoType
| ( LocalVarWoType ( , LocalVarWoType) + )
LocalVarWoType ::= [var ] Id
| Unpasting
Variables can be declared within block expressions (described in Section 13.11) via the same syntax as is used for
top-level variable declarations (described in Section 6.2). A local variable declaration must not appear as the last of
the block expression.
6.4 Local Function Declarations
Syntax:
LocalVarFnDecl ::= Id ValParam [IsType] [Throws] = Expr
Functions can be declared within block expressions (described in Section 13.11) via the same syntax as is used for toplevel
function declarations (described in Chapter 12) except that locally declared functions must not include modifiers,
contracts, static parameters, or where clauses (described in Chapter 11). As with top-level function declarations,
locally declared functions in a single scope are allowed to be overloaded and mutually recursive. A local function
declaration must not appear as the last of the block expression.
6.5 Matrix Unpasting
Syntax:
Unpasting ::= [ L-Elt (Paste L-Elt) ∗ ]
L-Elt ::= Id [[ L-ArraySize ]]
| Unpasting
L-ArraySize ::= L-Extent (×L-Extent) ∗
L-Extent ::= Expr
| Expr : Expr
| Expr # Expr
Paste ::= (Whitespace | ; ) +
Matrix unpasting is an extension of variable declaration syntax as a shorthand for breaking a matrix into parts. On
the left-hand side of a declaration, what looks like a matrix pasting of unbound variables is actually a declaration of
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