Julia: Making derived type objects with parameters

instance_factory.jl

abstract type baseType end

function call( ::Type{T}, params... ) where T <: baseType
    return T( params... )
end
# call (generic function with 1 method)

type derived1 <: baseType
    x::Int64
    y::Float64
    
    function derived1( x::Int64, y::Float64 )
        new( x, y )
    end
end

type derived2 <: baseType
    x::Int64
    y::Float64
    z::Float64
    
    function derived2( x::Int64, y::Float64, z::Float64 )
        new( x, y, z )
    end
end

x1 = derived1( 2, 3.0 )
x2 = derived2( 3, 3.0, 4.0 )
# derived2(3, 3.0, 4.0)

function factory( ::Type{T}, params... ) where T <: baseType
    return call( T, 2, params... )
end
# factory (generic function with 1 method)

factory( derived1, 2.0 )
# derived1(2, 2.0)

factory( derived2, 1.0, 2.2 )
# derived2(2, 1.0, 2.2)

z = Vector{baseType}()
push!( z, derived1(2,12.0) )
# 1-element Array{baseType,1}:
#  derived1(2, 12.0)

x = Dict( derived1 => (2.0), derived2 => (3.0,4.0) )
# Dict{DataType,Any} with 2 entries:
#   derived1 => 2.0
#   derived2 => (3.0, 4.0)

for (k,v) in x
    push!( z, factory(k,v...) )
end 

z
# 3-element Array{baseType,1}:
#  derived1(2, 12.0)    
#  derived1(2, 2.0)     
#  derived2(2, 3.0, 4.0)

w = Vector{baseType}()
for (k,v) in x
#     push!( w, call( k, 2, v... ) )
    push!( w, k( 2, v... ) )
end
# 2-element Array{baseType,1}:
#  derived1(2, 2.0)     
#  derived2(2, 3.0, 4.0)