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So I'm following the book Learning Perl, there's this code with comments in it:
$rocks[0] = 'bedrock'; $rocks[1] = 'slate'; $rocks[2]= 'lava'; $rocks[3] = 'crushed rock'; $rocks[99] = 'schist'; $#rocks = 2; # forget all rocks after 'lava' $#rocks = 99; # add 97 undef elements (the forgotten rocks are gone fo +rever)
If I do print $rocks[$#rocks]; it prints nothing. Why? When I comment out $#rocks = 99; it prints 'lava' and when I comment out $#rocks = 2; it prints 'schist'. But when I maintain the two it prints nothing as I already said. And what the comments "add 97 undef elements (the forgotten rocks are gone forever)" and "forget all rocks after 'lava'" mean?

In reply to What's going on in array element assignment? by zapdos

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