Re: sub execution order aka missing semicolon after sub call

That's because without the semicolon, Perl understands the code as

sub_A(sub_B());
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as you can easily verify with B::Deparse:

$ perl -MO=Deparse,-p ~/1.pl
sub sub_A {
    use warnings;
    use strict;
    print("sub_A\n");
}
sub sub_B {
    use warnings;
    use strict;
    print("sub_B\n");
}
use warnings;
use strict;
sub_A(sub_B());
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My advice is you should get into the habit of always using parentheses for function calls.

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
[download]

Comment on Re: sub execution order aka missing semicolon after sub call Select or Download Code

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Re^2: sub execution order aka missing semicolon after sub call by jmaas (Initiate) on Apr 06, 2016 at 15:41 UTC
Thanks to all repliers. The idea with the habit of adding () after all sub-calls is indeed a very good idea.	[reply]
Re^3: sub execution order aka missing semicolon after sub call by johngg (Canon) on Apr 07, 2016 at 10:41 UTC
The idea with the habit of adding () after all sub-calls is indeed a very good idea. There is a special case where the use of parentheses is not appropriate. If you call `subB` from within `subA` using the syntax `&subB` with no parentheses then the argument list of `subA` will be passed to `subB`. See this node for an example. The subroutine doesn't actually have to be called from within another subroutine; it is the content of `@_` that matters, as demonstrated by the following code. `$ perl -Mstrict -Mwarnings -E ' @_ = @ARGV; ∑ sub sum { my $sum; $sum += $_ for @_; say $sum; }' 1 2 3 4 5 15 $` [download] I hope this is of interest. Cheers, JohnGG	[reply] [d/l] [select]