The `getindex` explanation is not quite correct. Note, for instance, that
Avik's example returns a 1-element array containing the tuple (1, 2, 3),
not the 3-element array [1, 2, 3].
As far as *callable* objects are concerned, I think you probably want
`vcat` (or 'hcat', depending on your case):
*julia> **apply(vcat, 1, 2, 3)*
*WARNING: apply(f, x) is deprecated, use `f(x...)` instead*
in depwarn at ./deprecated.jl:62
in apply at deprecated.jl:115
while loading no file, in expression starting on line 0
*3-element Array{Int64,1}:*
* 1*
* 2*
* 3*
HOWEVER, it's worth noting that most array construction actually does not
go through a callable object, but rather is the result of parsing an
expression with a special head. Dumping expressions containing common array
construction patterns will be more revealing here than looking at methods:
*julia> **dump( :( [1, 2, 3, 4] ))*
Expr
head: Symbol vect
args: Array(Any,(4,))
1: Int64 1
2: Int64 2
3: Int64 3
4: Int64 4
typ: Any
*julia> **dump( :( [1 2 3 4] ))*
Expr
head: Symbol hcat
args: Array(Any,(4,))
1: Int64 1
2: Int64 2
3: Int64 3
4: Int64 4
typ: Any
*julia> **dump( :( Int[1; 2; 3; 4] ))*
Expr
head: Symbol typed_vcat
args: Array(Any,(5,))
1: Symbol Int
2: Int64 1
3: Int64 2
4: Int64 3
5: Int64 4
typ: Any
*julia> **eval(Expr(:vcat, 1, 2, 3, 4))*
*4-element Array{Int64,1}:*
* 1*
* 2*
* 3*
* 4*
On Wednesday, June 17, 2015 at 8:54:11 AM UTC-4, Mauro wrote:
>
> I think it just uses getindex (a bit of a hack...):
>
> julia> @which Int[3]
> getindex(T::Union(DataType,UnionType,TypeConstructor),vals...) at
> array.jl:119
>
>
> On Wed, 2015-06-17 at 14:50, andrew cooke <[email protected] <javascript:>>
> wrote:
> > Oh, I think the call() thing is just me being confused. That's *only* a
> > mechanism to allow non-functions to look like functions? I guess my
> > misunderstanding is more about how apply is defined (it mentions call),
> > which really isn't important to me right now, so feel free to ignore
> that
> > part of my question. Sorry.
> >
> >
> > On Wednesday, 17 June 2015 09:45:46 UTC-3, andrew cooke wrote:
> >>
> >>
> >> If I want to pass the function that constructs an array of Any, given
> some
> >> values, to another function, what do I use?
> >>
> >> Here's an example that might make things clearer:
> >>
> >> julia> f(x...) = Any[x...]
> >> f (generic function with 1 method)
> >>
> >> julia> apply(f, 1,2,3)
> >> 3-element Array{Any,1}:
> >> 1
> >> 2
> >> 3
> >>
> >> julia> apply(Any[], 1,2,3)
> >> ERROR: MethodError: `call` has no method matching call(::Array{Any,1},
> ::
> >> Int64, ::Int64, ::Int64)
> >> Closest candidates are:
> >> BoundsError(::Any...)
> >> TypeVar(::Any...)
> >> TypeConstructor(::Any...)
> >> ...
> >> in apply at deprecated.jl:116
> >>
> >> where I am looking for what the built-in equivalent of f() is.
> >>
> >> I may be even more confused, because I also don't understand why this
> >> fails:
> >>
> >> julia> call(f, 1, 2)
> >> ERROR: MethodError: `call` has no method matching call(::Function,
> ::Int64
> >> , ::Int64)
> >> Closest candidates are:
> >> BoundsError(::Any...)
> >> TypeVar(::Any...)
> >> TypeConstructor(::Any...)
> >> ...
> >>
> >> So any guidance appreciated.
> >>
> >> Thanks,
> >> Andrew
> >>
>
>
