Basically that opinion shows faulty but questions still remains. When is $i evaled? Or in what dictionary/environment/whatever-mechanism-is-used?

In your case, $i is evaluated when the string containing a literal '$i' is eval()ed. You could evaluate $i earlier by interpolating $i into the string (evaluating $i when the string is created), but then, that would convert the value of $i into a string, which isn't always what you want: 

makeLazy(qq(print "\nnow its $i"));

[download]
Note that this also decouples the eval'd code in makeLazy from the actual current value of $i.

Because of the same problem i run into with my code (but i didnt knew until now that it was the same problem): if you defer the declaration of $i then you get Global symbol "$i" requires explicit package name
Well, what do you want it to do? Either you want a lexical variable, but then you must declared it in its lexical scope, or you may want a (possibly local()ized package variable) - which you don't have to declare, if you prepend them with the package name (or you *could* switch of strict 'vars').

update: Note that in my alternative version, using my $defer = sub  { something_with($i) } syntax, $i is evaluated when $defer->() is called, but the scoping of $i is resolved at compile time, and figuring out the actual instance of $i may be resolved when the $defer = .. assignment is executed (that last part is important if you're generating these $defer closures from within another subroutine, with $i declared lexical in the outer subroutine).

You may find this column useful

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re^3: Not-so-lazy evaluation? by Joost
in thread Not-so-lazy evaluation? by mtroost

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