I once built a Julia varargs-to-C varargs function, which even though there
was a better way to accomplish the same goal, I saved as an example for myself
in case I needed it in the future. See if it's helpful to you.
--Tim
const GtkFileChooserDialogDict = Dict{Int, Function}() # for varargs ccall
type GtkFileChooserDialog <: GtkDialogI
handle::Ptr{GObject}
function GtkFileChooserDialog(title::String,
parent::Union(GtkWindow,Ptr{Void}), action::Integer, button_text_response...)
n = length(button_text_response)
if !iseven(n)
error("button_text_response must consist of text/response pairs")
end
npairs = div(n, 2)
if !haskey(GtkFileChooserDialogDict, npairs)
# Build a function expression that makes ccall with explicit args
of correct types
ctypeexpr = Expr(:tuple,Ptr{Uint8},Ptr{Void},Cint,ntuple(n,i-
>isodd(i) ? Ptr{Uint8} : Cint)...,Ptr{Void})
argnameexpr = Expr(:tuple,:title,:parent,:action,Expr(:...,
:button_text_response))
argvalexpr = tuple(:title,:(anonp(parent)),:action,ntuple(n,i->:
(button_text_response[$i]))...,:C_NULL)
ex = Expr(:function, argnameexpr, Expr(:ccall,
:
(:gtk_file_chooser_dialog_new,libgtk),
:(Ptr{GObject}),
ctypeexpr,
argvalexpr...))
GtkFileChooserDialogDict[npairs] = eval(ex)
end
hnd = GtkFileChooserDialogDict[npairs](title, parent, action,
button_text_response...)
widget = gc_ref(new(hnd))
gtk_doevent()
show(widget)
widget
end
end
On Tuesday, June 10, 2014 03:09:31 PM J Luis wrote:
> Hi,
>
> How would I turn this C function prototype into a ccall?
>
> Ihandle* IupVbox(Ihandle **child*, ...);
>
> The varargs here mean that all but last optional arguments are of the same
> type a `child`. The last one must be NULL.
> Let me also add that Clang.jl skipped these type of declarations
