First i have a question not explicitatedd in the original node, about the clearing routine: if i modify my trigger function to manage undef values as in 
sub trigger{print "Triggered: ",map {defined $_ ? " $_" : 'UNDEF'}@_,"
+\n"}

[download]
When i try to @arr=undef the tie'magic is called twice. Why? 
# rest of the code as before..
print "\tclearing with undef \@arr:\n"     and   undef @arr;
print "\tSetting list:\n" and @arr = qw(a);
print "\tclearing with \@arr=undef:\n"     and   @arr=undef;
print "\tSetting list:\n" and @arr = qw(a);
print "\tclearing with \@arr=():\n"     and   @arr=();

__OUT__
        clearing with undef @arr:
Triggered:  Arraytrigger=ARRAY(0x6ab224)
        Setting list:
Triggered:  Arraytrigger=ARRAY(0x6ab224)
Triggered:  Arraytrigger=ARRAY(0x6ab224) 0 a
        clearing with @arr=undef:
Triggered:  Arraytrigger=ARRAY(0x6ab224)
Triggered:  Arraytrigger=ARRAY(0x6ab224) 0UNDEF
        Setting list:
Triggered:  Arraytrigger=ARRAY(0x6ab224)
Triggered:  Arraytrigger=ARRAY(0x6ab224) 0 a
        clearing with @arr=():
Triggered:  Arraytrigger=ARRAY(0x6ab224)

[download]
Second question: why the code is not triggered when i do a reference to some tied array's elements? 
my $ref = \$arr[0];
print "\tsetting by reference:\n"     and   $ref=11;

__OUT__
        setting by reference:

[download]
Third and more important, why i'm no more able to print my array? nor dump or dd it? a simply 
print "\@arr [@arr]\n";

[download]
put before clearing the array simply make my program hang, while eating lot of memory in with my Strawberry perl 5.14.2?

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.

In reply to Re: Is tie inteded to be used in this way? Few question arise by Discipulus
in thread Is tie inteded to be used in this way? by Discipulus

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