There's also an open issue about "splitting" or "splatting" of tuples 
within function arguments that's very relevant here: Allow tuple 
destructuring in formal arguments, 
https://github.com/JuliaLang/julia/issues/6614

It's a common use case that I run into often, especially with enumerate and 
dictionaries.  So you're not alone.

On Thursday, June 19, 2014 3:57:33 AM UTC-4, gentlebeldin wrote:
>
> Ah, I see, multiple dispatch is the real cause. I'll have to live with the 
> little ideosyncrasy, then.
> Peter's idea filter(p -> +(p...)%4 != 0, pairs) works fine... in my simple 
> example. In real life, I wanted to filter an array d of integers, with a 
> predicate
> i<=n && d[i]!=i && d[d[i]]==i, so filter((i,v)->i<=n && v!=i && 
> d[v]==i,enumerate(d)) looked like a reasonable idea, it just doesn't work. 
> We can make it work, though that looks a bit strange, too:
> filter([e for e in enumerate(d)]) do x
>        i,v=x
>        i<=n && v!=i && d[v]==i       
>        end
> Here, it looks as if the function filter took only one argument. It works, 
> however. In my code, I had to sum up the values of i after filtering, so I 
> chose the obscure formulation
> sum(map(first,filter(x->x[1]!=x[2] && x[2]<=n && 
> d[x[2]]==x[1],enumerate(d))))
>
>>
>>>

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