Maybe this is helpful?
I don't think your first example helps answer the op's question. Did the gc destroy the objects immediately after you undefined $head or did the gc merely mark them as ready for destruction, and then when the program ended the memory was released?
Some evidence from "Intermediate Perl (2nd)", p. 257:
To do the proper cleanup operations when Perl destroys an object, we need to know when that happens. Thankfully, Perl provides such notification upon request. We can request this notification by giving the object a DESTROY method.
When the last reference to an object, say $bessie, disappears, Perl invokes that objectís DESTROY method automatically, *as if we had called it ourselves*:
This method call is like most other method calls: Perl starts at the class of the object and works its way up the inheritance hierarchy until it finds a suitable method. However, unlike most other method calls, thereís no error if Perl doesnít find a suitable method.
That suggests that DESTROY is called immediately after the reference count goes to 0--in other words the object is not merely marked for destruction with DESTROY being called at the gc's leisure.
Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
Read Where should I post X? if you're not absolutely sure you're posting in the right place.
Please read these before you post! —
Posts may use any of the Perl Monks Approved HTML tags:
Outside of code tags, you may need to use entities for some characters:
- a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
Link using PerlMonks shortcuts! What shortcuts can I use for linking?
See Writeup Formatting Tips and other pages linked from there for more info.
| & || & |
| < || < |
| > || > |
| [ || [ |
| ] || ] ||