C++ - Most efficient way to remove an element from a Message's repeated array

[jaypipes]

Hi all,

I'm wondering what is the most efficient method to remove an element
from a Message's vector of repeated elements? I looked at the
RepeatedFieldPtr API but would appreciate some example code on how to
do this in the most efficient way. I gather from the API that the
underlying storage is a vector and so does not support efficient index-
based, random-access deletion from the vector. Is this correct?

Help is much appreciated,

Jay
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[Kenton Varda]

Post by jaypipes
I'm wondering what is the most efficient method to remove an element
from a Message's vector of repeated elements? I looked at the
RepeatedFieldPtr API but would appreciate some example code on how to
do this in the most efficient way. I gather from the API that the
underlying storage is a vector and so does not support efficient index-
based, random-access deletion from the vector. Is this correct?

Yes, that is correct.

The most efficient solution is to permute the contents so that the things
you want to remove are at the end, then use RemoveLast().

Note that the underlying storage is an array of *pointers*, so re-arranging
pointers doesn't require copying whole message objects.

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[jaypipes]

Gotcha. Thanks for the assistance, Kenton!
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