On 7/31/07, Rodrigo Tavares <[EMAIL PROTECTED]> wrote:
> Hello John,
>
> You could explain the below line ?
>
> print join( ',', ( $arrow[ $_ ] ) x ( $_ + 1 ) ),
> "\n";
snip
x is the repetition operator.
When the left side is a scalar it builds a string that contains the
left side repeated the right side times: "a" x 5 == "aaaaa". When
the left side is a list it creates a list with each element repeated
the right side times (in the original order): (1, 2, 3) x 3 == (1, 2,
3, 1, 2, 3, 1, 2, 3). So in the example above $_ is the offset into
the array. For the first element it is 0 so we have
print join(",", ($arrow[0]) x 1), "\n";
which is the same as
print join(",", $arrow[0]), "\n";
for the second element $_ is 1 so we have
print join(",", ($arrow[1]) x 2), "\n";
which is the same as
print join(",", $arrow[1], $arrow[1]), "\n";
for the third element $_ is 2 so we have
print join(",", ($arrow[2]) x 3), "\n";
which is the same as
print join(",", $arrow[2], $arrow[2], $arrow[2]), "\n";
and so on.
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