Re: Use hashes instead of grep

I agree that, all else being equal, this would be the best design.

However, it ultimately depends on what the rest of the code does.

When's the last time you used duct tape on a duct? --Larry Wall

Comment on Re: Use hashes instead of grep
Re^2: Use hashes instead of grep by space_monk (Hermit) on Nov 15, 2012 at 10:55 UTC
Not really. Even if the code uses both arrays then there is nothing preventing building a temporary hash through `my %hash = map { $_ => 1 } @first_list;` [download] ..and then discarding the hash after the check for new machines. More likely is that he is only interested in the second list, or just new machines, and they could be in an array just like before. A Monk aims to give answers to those who have none, and to learn from those who know more.	[reply] [d/l]
Re^3: Use hashes instead of grep by ColonelPanic (Friar) on Nov 15, 2012 at 11:15 UTC
Yes, but this method is not clearly superior if arrays are needed for other purposes. The array comparison is simpler, uses less memory, and will be fast unless both files are huge. When's the last time you used duct tape on a duct? --Larry Wall	[reply]
Re^4: Use hashes instead of grep by space_monk (Hermit) on Nov 15, 2012 at 14:01 UTC
The code to implement the hash version isn't significantly more complex - see the version in another nodelet for how it would go. A Monk aims to give answers to those who have none, and to learn from those who know more.	[reply]
Re^4: Use hashes instead of grep by Anonymous Monk on Nov 15, 2012 at 14:18 UTC
Or, as Darth put it: The time to build the structure is insignificant compared to the power of the hash!	[reply]


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