Feedback on my understanding of the five Named blocks

stevieb has asked for the wisdom of the Perl Monks concerning the following question:

Instead of requesting help with writing code, I'm looking for feedback on my understanding of code.

I've written a short usage-case document for BEGIN and END, and am wondering if there are people who care to review it so that my understanding can be confirmed or corrected prior to sharing it in a better location.

The doc is in ~~my scratchpad~~ a more stable place.

If this is not the place to request such feedback, I apologize, and I'll know for next time :)

Steve

Comment on Feedback on my understanding of the five Named blocks

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Re: Feedback on my understanding of the five Named blocks by JavaFan (Canon) on Apr 03, 2012 at 20:52 UTC
Here's a variation on one of your examples that show the difference between `INIT` and `BEGIN`: `use 5.010; use strict; use warnings; persist(); INIT { my $store = init_store(); sub persist { say $store++; } } persist(); persist(); sub init_store { 0 } __END__ 0 1 2` [download] But if you change the `INIT` into a `BEGIN`, you get a run-time error: `Undefined subroutine &main::init_store called at /tmp/xxx line 10. BEGIN failed--compilation aborted at /tmp/xxx line 14.` [download]	[reply] [d/l] [select]
Re^2: Feedback on my understanding of the five Named blocks by stevieb (Canon) on Apr 03, 2012 at 21:01 UTC
This is a wonderful distinction between the two, thank you for the addition! I'll certainly factor this in :)	[reply]
Re: Feedback on my understanding of the five Named blocks by GrandFather (Saint) on Apr 03, 2012 at 21:03 UTC
The Meditations section would probably be a better section for a "Request For Comment" (RFC). By convention such a node's title is prefixed "RFC:". Don't include links to material that may be transient. Put the material in your node instead. PerlMonks nodes are a resource that are referred back to for years. It's a real pain if the key information in the node has vanished because it was linked and the link has broken or the material has been altered. True laziness is hard work	[reply]
Re: Feedback on my understanding of the five Named blocks by Anonymous Monk on Apr 03, 2012 at 21:26 UTC
See also What is the difference between a Statement and an Expression? `perldoc compile` `perldoc perlcompile` Execution order of END/CHECK vs BEGIN/INIT INIT blocks and runtime code loading What is an INIT block? CHECK and INIT under mod_perl BEGIN, END, eval and die. eval() and INIT{} Which phase am I in?	[reply]