TypeScript Language Specification v1.5

Tuple types assign numeric names to each of their elements and elements are therefore strongly typed
when accessed using bracket notation with a numeric literal:
var data: [string, number] = ["five", 5];
var s = data[0]; // string
var n = data[1]; // number
4.11 The new Operator
A new operation has one of the following forms:
new C
new C ( ... )
new C < ... > ( ... )
where C is an expression. The first form is equivalent to supplying an empty argument list. C must be of
type Any or of an object type with one or more construct or call signatures. The operation is processed as
follows at compile-time:
If C is of type Any, any argument list is permitted and the result of the operation is of type Any.
If C has one or more apparent construct signatures (section 3.10.1), the expression is processed in
the same manner as a function call, but using the construct signatures as the initial set of
candidate signatures for overload resolution. The result type of the function call becomes the
result type of the operation.
If C has no apparent construct signatures but one or more apparent call signatures, the
expression is processed as a function call. A compile-time error occurs if the result of the function
call is not Void. The type of the result of the operation is Any.
4.12 Function Calls
Function calls are extended from JavaScript to optionally include type arguments.
Arguments: ( Modified )
TypeArguments opt ( ArgumentList opt )
A function call takes one of the forms
func ( ... )
func < ... > ( ... )
where func is an expression of a function type or of type Any. The function expression is followed by an
optional type argument list (section 3.5.2) and an argument list.
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