Why $-reference possible to Perl array? -


this question has answer here:

i thinking how can refer element in perl array sign $.

minimum code

my @x = @{ $_[0] };   for(my $i=0; $i<$#x; $i++){     print $x[$i];  }

you initialize array @x array. print out each item array $x[$i] in loop.

i think bit confusing when initialize array @x , size $#x.

why can refer perl array $x?

because perlish way have sigil denoting type of thing you're working with, rather being part of variable name.

$x scalar, unrelated list @x. $x[1] still scalar - it's element from list @x. (and unrelated $x, because - couldn't pick single element out of single element).

$#x single value (scalar) has $ prefix still.

the same applies hashes. %hash whole hash. $hash{$key} single value hash. , @hash{@some_keys} list of values hash.


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