Dynamically call function with the specified arguments.
Acts the same as calling function with positional arguments
corresponding to the elements of positionalArguments and
named arguments corresponding to the elements of namedArguments.
This includes giving the same errors if function isn't callable or
if it expects different parameters.
Example:
Map<Symbol, dynamic> namedArguments = new Map<Symbol, dynamic>();
namedArgumentsconst Symbol("f") = 4;
namedArgumentsconst Symbol("g") = 5;
Function.apply(foo, 1,2,3, namedArguments);
gives exactly the same result as foo(1, 2, 3, f: 4, g: 5).
If positionalArguments is null, it's considered an empty list.
If namedArguments is omitted or null, it is considered an empty map.
Source
external static apply(Function function, List positionalArguments,
[Map<Symbol, dynamic> namedArguments]);