Skip() on IReadOnlyList needlessly enumerates skipped items

[vsfeedback]

This issue has been moved from a ticket on Developer Community.

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[severity:It's more difficult to complete my work]
If you call .Skip() on a collection that implements IReadOnlyList but doesn't implement IList, Skip needlessly enumerates all skipped items, whereas on an IList implementation, it makes use of the indexer and does not enumerate the skipped items. This is needlessly inefficient.

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Original Comments

TRI-L Data Systems Claudio Friederich on 3/29/2022, 05:35 PM:

(private comment, text removed)

Feedback Bot on 3/29/2022, 11:11 PM:

(private comment, text removed)

Fiona Niu[MSFT] on 6/30/2022, 01:37 AM:

(private comment, text removed)

TRI-L Data Systems Claudio Friederich on 7/11/2022, 02:32 PM:

(private comment, text removed)

TRI-L Data Systems Claudio Friederich on 7/11/2022, 03:23 PM:

(private comment, text removed)

Feedback Bot on 7/6/2022, 11:51 PM:

(private comment, text removed)

Feedback Bot on 7/11/2022, 11:38 PM:

(private comment, text removed)

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Original Solutions

(no solutions)

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[ghost]

Tagging subscribers to this area: @dotnet/area-system-linq
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Issue Details

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This issue has been moved from a ticket on Developer Community.

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[severity:It's more difficult to complete my work]
If you call .Skip() on a collection that implements IReadOnlyList but doesn't implement IList, Skip needlessly enumerates all skipped items, whereas on an IList implementation, it makes use of the indexer and does not enumerate the skipped items. This is needlessly inefficient.

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Original Comments

TRI-L Data Systems Claudio Friederich on 3/29/2022, 05:35 PM:

(private comment, text removed)

Feedback Bot on 3/29/2022, 11:11 PM:

(private comment, text removed)

Fiona Niu[MSFT] on 6/30/2022, 01:37 AM:

(private comment, text removed)

TRI-L Data Systems Claudio Friederich on 7/11/2022, 02:32 PM:

(private comment, text removed)

TRI-L Data Systems Claudio Friederich on 7/11/2022, 03:23 PM:

(private comment, text removed)

Feedback Bot on 7/6/2022, 11:51 PM:

(private comment, text removed)

Feedback Bot on 7/11/2022, 11:38 PM:

(private comment, text removed)

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Original Solutions

(no solutions)

Author:	vsfeedback
Assignees:	-
Labels:	area-System.Linq, untriaged
Milestone:	-

[eiriktsarpalis]

Duplicate of #24793. Closing in favor of #42254 which holds a broader conversation on collection interface optimizations.