Can FunctionWrappers.jl express higher order functions?

General Usage
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By the way, this overly verbose syntax is a great excuse to write a macro:

using MacroTools
using FunctionWrappers: FunctionWrapper

wrapperize(x) = esc(x)

function wrapperize(expr::Expr)
	if expr.head == :block
		return Expr(:block, wrapperize.(expr.args)...)
	elseif expr.head == :tuple
		return Expr(:tuple, wrapperize.(expr.args)...)
	elseif @capture(expr, (inputs__,) -> output_)
		return :(FunctionWrapper{$(wrapperize(output)), Tuple{$(wrapperize.(inputs)...)}})
	elseif @capture(expr, (input_) -> output_)
		return :(FunctionWrapper{$(wrapperize(output)), Tuple{$(wrapperize(input))}})
	else
		error("I can only handle expressions of the form `(inputs...) -> output`")
	end
end

macro fn(expr)
	wrapperize(expr)
end

Examples:

julia> @fn Int -> Int
FunctionWrapper{Int64, Tuple{Int64}}

julia> @fn (Int, Float64) -> Int
FunctionWrapper{Int64, Tuple{Int64, Float64}}

julia> @fn (Float64, Int -> Int) -> String
FunctionWrapper{String, Tuple{Float64, FunctionWrapper{Int64, Tuple{Int64}}}}
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