Re^6: Deleting specific array elements

Thanks for that and am not aware of such a context reasoning

One more question
for (my $i = 0; $i < @molecules; $i ++) {
Instead of the above

my $num_elements = scalar(@molecules);
for (my $i = 0; $i < $num_elements; $i++) {
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will that bring any performance improvement or the number of elements of an array is stored internally ( in some scalar ) and there is no need to evaluate it again ?

Thanks again for the reply! :)

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Re^7: Deleting specific array elements by JavaFan (Canon) on Nov 27, 2008 at 10:37 UTC
There's no significant speed difference. For both the scalar and the array, the get to the integer value from the SV or AV, one has to walk a pointer and add an offset. It may even be that in the scalar case, perl checks IOK flag each time (to see whether it actually has a valid integer value), but that maybe optimized away. Anyway, there isn't much of a reason to store the length of an array in a seperate variable.	[reply]

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Re^7: Deleting specific array elements
by JavaFan (Canon) on Nov 27, 2008 at 10:37 UTC

It may even be that in the scalar case, perl checks IOK flag each time (to see whether it actually has a valid integer value), but that maybe optimized away.

Anyway, there isn't much of a reason to store the length of an array in a seperate variable.

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