guardFunction()
guardFunction()
guardFunction()
Guards the value to be a Function
.
Generic type variables
Type
extends
Function
Type
extends
Function
A generic type variable Type
constrained by Function
indicates captured function
type of the given value
via the return type and the value
parameter of the provided callback
function ResultCallback
type.
Payload
extends
object
=
object
Payload
extends
object
=
object
The Payload
generic type variable constrained by object
indicates the type of optional parameter payload
of the supplied callback
function and payload
optional parameter of the guardFunction()
function from which it captures its value.
Parameters
value: Type
value: Type
The function
of a generic type variable Type
to guard.
callback?: ResultCallback<Type, Payload>
callback?: ResultCallback<Type, Payload>
The optional callback function
of ResultCallback
type with parameters, the value
that has been checked, the result
of this check, and payload
of generic type variable Payload
with optional properties from the provided payload
, to handle them before the result
return. By default, it uses resultCallback()
function.
payload?: Payload
payload?: Payload
An optional object
of the generic type variable Payload
is assigned to the payload
of the given callback
function.
Return type
value is Type
value is Type
The return type is a boolean
as the result of its statement indicating the value
is a generic type variable Type
by default equal to the type captured from the supplied value
.
Returns
The return value is a boolean
indicating whether the value
is a Function
.
Example usage
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