TypeScript Language Specification

The JavaScript code generated for a super property access is specified in section 8.5.2.
4.9 Function Expressions
Function expressions are extended from JavaScript to optionally include parameter and return type
annotations, and a new compact form, called arrow function expressions, is introduced.
FunctionExpression: ( Modified )
function Identifieropt CallSignature { FunctionBody }
AssignmentExpression: ( Modified )
…
ArrowFunctionExpression
ArrowFunctionExpression:
ArrowFormalParameters => Block
ArrowFormalParameters => AssignmentExpression
ArrowFormalParameters:
CallSignature
Identifier
The terms standard function expression and arrow function expression are used to refer to the
FunctionExpression and ArrowFunctionExpression forms respectively. When referring to either, the generic
term function expression is used.
The type of a function expression is an object type containing a single call signature with parameter and
return types inferred from the function expression’s signature and body.
The descriptions of function declarations provided in section 6.1 apply to function expressions as well,
except that function expressions do not support overloading.
Function expressions with no parameter or return type annotations (but possibly with optional parameters
and default parameter values) are contextually typed in certain circumstances, as described in section
4.18. When a function expression is contextually typed by a function type T, the function expression is
processed as if it had explicitly specified parameter and return type annotations as they exist in T.
Parameters are matched by position and need not have matching names. If the function expression has
fewer parameters than T, the additional parameters in T are ignored. If the function expression has more
parameters than T, the additional parameters are all considered to have type Any.
4.9.1 Standard Function Expressions
Standard function expressions are function expressions written with the function keyword. The type of
this in a standard function expression is the Any type.
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