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Re^3: The Concept of References

by dragonchild (Archbishop)
on Apr 14, 2005 at 12:43 UTC ( #447737=note: print w/ replies, xml ) Need Help??

in reply to Re^2: The Concept of References
in thread The Concept of References

You don't, because doing so would violate the guarantee that you cannot buffer overflow in Perl. But, there are good reasons why C gives you the rope to buffer overflow.

Let's say you want to iterate through the characters of a string and do something with each character. In C, that's pretty simple. Strings are just arrays of characters and arrays are just fancy pointers.

char string[] = "Hello"; char *ptr; fr ( ptr = string; *ptr; ptr++ ) { do_something_with( *ptr ); // This is a single char }
Now, let's say you want to do the same thing in Perl. There's a few ways, but none are anywhere as efficient.
foreach my $char ( split //, $string ) { ... } while ( $string =~ /(.)/g ) { my $char = $1; ... } for ( my $i = 0; $i <= length $string; $i++ ) { my $char = substr( $st +ring, $index, 1 ); ... }

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