In 12.6.1 of n2521, it says:
"When an aggregate (whether class or array) contains
members of class type and is initialized by a brace-
enclosed initializer list, each such member is
copy-initialized by the corresponding assignment-expression."
Then the example is given:
complex v[6] = { 1, complex(1,2), complex(), 2 };
where 'complex' is a small class defined in the 12.6
for exemplary purposes.
According to the above paragraph, v[1] should be
copy-constructed from the temporary complex(1,2).
However, the explanation of the example code says:
"complex::complex(double,double) is called for the
initialization of v[1]".
That is, it says that v[1] is directly constructed with
arguments 1,2, and no copy constructor is involved.
Is the example rationale wrong, or have I misinterpreted
the paragraph quoted above?
1  1288 
On Sep 1, 9:40*am, Old Wolf <oldw...@inspire.net.nzwrote:
In 12.6.1 of n2521, it says:
* "When an aggregate (whether class or array) contains
* members of class type and is initialized by a brace-
* enclosed initializer list, each such member is
* copy-initialized by the corresponding assignment-expression."
Then the example is given:
* complex v[6] = { 1, complex(1,2), complex(), 2 };
where 'complex' is a small class defined in the 12.6
for exemplary purposes.
According to the above paragraph, v[1] should be
copy-constructed from the temporary complex(1,2).
However, the explanation of the example code says:
* "complex::complex(double,double) is called for the
* initialization of v[1]".
That is, it says that v[1] is directly constructed with
arguments 1,2, and no copy constructor is involved.
Is the example rationale wrong, or have I misinterpreted
the paragraph quoted above?
I think it means that before the copy constructor is called, '1' has
to be converted to complex first, which is done by calling the
constructor complex::complex(double, double) (A.K.A. implicite
conversion) This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics
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