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= default { body... } on constructors and operator=

From: Bengt Gustafsson <bengt.gustafsson_at_[hidden]>
Date: Wed, 24 Feb 2021 16:43:57 +0100
It seems rather common that move constructors and move assignment
operators need to first move all members and then just set one member in
the source to indicate that it has been moved from. Couldn't we allow a
body after = default to handle this situation. Here is today's example:


|RasterIO::RasterIO(RasterIO&& src) :
m_fileName(std::move(src.m_fileName)), m_fileHandle(src.m_fileHandle),
m_headerSize(src.m_headerSize),
     m_footerSize(src.m_footerSize), m_type(src.m_type),
m_width(src.m_width), m_height(src.m_height), m_depth(src.m_depth),
     m_frames(src.m_frames), m_fileRowStride(src.m_fileRowStride),
     m_isRaw(src.m_isRaw), m_description(std::move(src.m_description))
{
     src.m_fileHandle = -1;
}|

|
|

|Which could be reduced to:|


|||RasterIO::|RasterIO(RasterIO&& src) = default {
     src.m_fileHandle = -1;
}||

||The current situation is both boring and reinstates the situation that
= default was intended to remove, i.e. the verbosity and error proneness.||

||For constructors it would be possible to also allow : <initializers>
between default and { which would allow special handling of a subset of
the members, but I think this would rather rarely be useful.||

||
||

||What do you think?||

||Bengt||

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Received on 2021-02-24 09:44:08