Hi all,
I've got an issue I don't really like in one of my modules, and I was
wondering the best thing (if anything) to do about it.
The module if for dependent bootstraps, but the problem is more of a
project design issue. I have a type for each bootstrap method, e.g.
`StationaryBootstrap`, `MovingBlockBootstrap` e.t.c. and they are all
sub-types of an abstract `BootstrapMethod`. Then I have functions that can
be called over these different bootstrap method types and multiple dispatch
will make sure the appropriate code is called, e.g
`bootindices(::StationaryBootstrap)` or
`bootindices(::MovingBlockBootstrap)`. This all works nicely.
I now want to define some keyword wrapper type functions in the module for
users who don't want to learn much about how the types within the module
work. For example, my wrapper might let the user describe the bootstrap
procedure they want with a string, eg `bootindices(...;
bootstrapmethod::ASCIIString="stationary")`.
The keyword wrapper is called, and I have a variable `bootstrapMethod`
which is a string. I need to convert it into the appropriate bootstrap
method type so I can then call the appropriate method via multiple
dispatch. Currently I have one function that does this and looks something
like this:
function boot_string_to_type(x::ASCIIString)
x == "stationary" && return(StationaryBootstrap())
x == "movingBlock" && return(MovingBlock())
...
end
The problem is that this function is not type-stable.
Should I be worried? Does anyone have a better way of dealing with this
kind of issue? Maybe something involving symbols or expressions, or
anonymous functions etc?
Note, the situation can sometimes get quite a bit more complicated than
this, with multiple key-word arguments, all of which need to be combined
into the constructor for the relevant type.
Cheers,
Colin
