UPDATE: Forget this node. I just saw that I have misread the docs. NO NEED TO RESPOND.

I have a sub which expects one or more arguments. In particular, the first argument could be (for instance) a number or a reference to an anonymous sub. Here are two valid examples for calling my function: 

f(15,103);
f(sub { print(4711); }, 1000, 1111);

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As syntactic sugar, I would like to have the possibility to specify the first argument as a code block, i.e. 

f  {print(4711);} 1000, 1111;

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I guess there is no alternative for using prototypes in this case.... However, I can not specify the prototype as f(&;@), since in this case the first argument must be a sub ref or code block, but in my case, it might also be a non-reference. Hence I tried to prototype my function like this: 
sub f(\[$&];@)

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I.e. a simple scalar or a code block, optionally followed by other arguments. Unfortunately this does not work. When invoking f as f(1,2,3,4), I get the error message Type of arg 1 to main::f must be one of [$&] (not constant item).

What am I doing wrong? I must misunderstand the explanations in perlsub about the the "\[]" notation prototype somehow...
-- 
Ronald Fischer <ynnor@mm.st>

In reply to Prototype question by rovf

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