Assuming I have a sub and this sub needs a variable which should have persistent value from call to call, i.e. something like in C++

// This is C++
void f() {
  static int myvar=myfunc(); // will be initialized only at the first 
+call of f()
  ...
  g(++myvar); // Incremented on every call
}
[download]

In Perl I have found the following solution to this problem:

sub f {
  our $myval;
  BEGIN { $myval=myfunc() };
  ...
  g(++$myval);
}
[download]

It is not 100% equivalent to the C++ example, because $myval is not really private to f. If another sub in the same package would also use our $myval, it would denote the same variable.

My questions are now:

• Aside from the weakness just mentioned, do you see any problem with this code? In particular, the BEGIN block inside a sub looks a bit strange to me, but it seems to work.
• Do you see better ways to solve this problem?

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