my $var

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

Thanks for all your answers and links . I am clear on lexical variables now.

Hello,
Say I have a program with 4 subs in it and one of the subs has --my $var-- set to something.
Will this var get cleaned after the sub is finished?
Will it only get cleaned after the whole program is finished ?
Will setting $| = 1; clear this var ?

Comment on my $var

Replies are listed 'Best First'.
Re: my $var by ikegami (Patriarch) on Nov 10, 2010 at 19:29 UTC
A lexical (`my`) variable get cleared when exiting the tightest lexical scope (curlies or file) in which it is found. `sub f { my $x = ...; { my $y = ...; ... # $y cleared here. } ... # $x cleared here. }` [download] It doesn't matter how the scope is exited. It'll get cleared on `return`, `die`, `next`, etc. You obviously didn't read the documentation for `$\|`.	[reply] [d/l] [select]
Re: my $var by superfrink (Curate) on Nov 10, 2010 at 19:31 UTC
Have a look at Lexical scoping like a fox	[reply]
Re: my $var by Anonymous Monk on Nov 10, 2010 at 19:40 UTC
Sounds like a homework assignment, therefore see Tutorials: Variables and Scoping	[reply]
Re: my $var by Anonymous Monk on Nov 10, 2010 at 19:34 UTC
A lexical variable -- a variable declared with my -- exists only while the scope its in is currently being executed. Perl uses reference counting for "garbage collection", if that helps you visualize the process. The global, built-in variable $\| allows you to turn on or off autoflush on the currently-selected output channel (STDOUT by default). This has nothing to do with lexical variables.	[reply]