BEGIN block

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

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Re: BEGIN block by Corion (Patriarch) on Oct 23, 2015 at 07:32 UTC
Most likely, right after the `BEGIN` block, there is another `use` statement. The assignments to `%ENV` are for the benefit of that next `use` statement (which implicitly also happens at `BEGIN` time). In the case of IO::Socket::SSL, this is to tell LWP::UserAgent the options to use with IO::Socket::SSL.	[reply] [d/l] [select]
Re: BEGIN block by Discipulus (Canon) on Oct 23, 2015 at 07:13 UTC
Probably to be sure the value are set before the module is loaded? Infact an `use` statement is exactly equivalent to: `BEGIN { require Module; Module->import( LIST ); }` [download] The only way to do something before this is use a BEGIN block just before the use statement L* There are no rules, there are no thumbs.. Reinvent the wheel, then learn The Wheel; may be one day you reinvent one of THE WHEELS.	[reply] [d/l] [select]
Re^2: BEGIN block by Laurent_R (Canon) on Oct 23, 2015 at 07:33 UTC
Yes, that's what a BEGIN block is generally about, but, in this case, it appears that this BEGIN block with these four assignments occurs after the `use IO::Socket::SSL;` statement, so that these assignments are executed afterwards.	[reply] [d/l]
Re^3: BEGIN block by Discipulus (Canon) on Oct 23, 2015 at 07:41 UTC
oops, it seems i've not seen the use statement! L* There are no rules, there are no thumbs.. Reinvent the wheel, then learn The Wheel; may be one day you reinvent one of THE WHEELS.	[reply] [d/l]
Re: BEGIN block by AnomalousMonk (Archbishop) on Oct 23, 2015 at 07:18 UTC
See "BEGIN, UNITCHECK, CHECK, INIT and END" section in perlmod. Give a man a fish: `<%-{-{-{-<`	[reply] [d/l]
Re: BEGIN block by Anonymous Monk on Oct 23, 2015 at 07:12 UTC
why the use of the BEGIN block ? why not just assign the $ENV values at runtime? So that it has effect at BEGIN time ( at use time) Maybe those specific %ENV values have no effect at runtime, maybe they only affect IO::Socket::SSL at BEGIN time (the docs ought to clarify this, check the docs)	[reply]