toString method
A string representation of this object.
Some classes have a default textual representation,
often paired with a static parse function (like int.parse).
These classes will provide the textual representation as
their string representation.
Other classes have no meaningful textual representation
that a program will care about.
Such classes will typically override toString to provide
useful information when inspecting the object,
mainly for debugging or logging.
Implementation
@override
String toString() {
final msg = (null != functionName)
? "The function '$functionName' returned an invalid result"
: "A function returned an invalid result";
if (null == description) return "$msg: $invalidResult";
return "$msg.\n$description:\n\n$invalidResult";
}