[Mono-list] foreach issues

[Pedro Santos]

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Hi, I was wondering what would be faster when using foreach: an
ArrayList ou an Array. At first, would be expected that foreach with an
ArrayList would be slower than with an array, and it is a lot slower.
But, doesn't foreach see the Array and the ArrayList has a IEnumerable?
Whouldnt it be the same in the foreach prespective?

It appears not to be, If I do the same, but pass an IEnumerable to the
foreach it is alot faster, in this case the foreach with the ArrayList
is faster.

The test is in attachement. This were the times:

bash-2.05b$ mono test.exe
foreach list:     : 00:00:00.0159550
foreach array:    : 00:00:00.0000420
IEnumerable list  : 00:00:00.0000830
IEnumerable array : 00:00:00.0001040

Can someonte elaborate on this? I am curious.

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Pedro Santos <www.psantos.net>
"Si minor plus est ergo nihil sunt omnia..."

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