how to initialize in struct declaration

[omerbrandis]

Hello Piotr

First I must thank you for creation, its really a must in the cpp space.

I'm using 1.18, and am unable to compile the following struct MyStruct { decimal<2> myVariable(0); }

also can't struct MyStruct { decimal<2> myVariable = 0; } error : could not convert ‘0’ from ‘int’ to ‘dec::decimal<2>’ ^

I can set a value in the constructor mil. this is a decent workaround , but less convenient for me at this time.

please advise, Omer.

[Kvaz1r]

Try this:

struct MyStruct
{
    decimal<2> myVariable{ 0 };
};

[omerbrandis]

it works , :-)

thank you Kvaz1r,

can you please tell me a bit more about what/why this is ?

thanks, Omer.

[vpiotr]

@omerbrandis The "0" is just an example or a real value? It looks like you are trying to investigate rules of initialization which can be very complicated - if you do not provide your own constructor. Solution from @Kvaz1r probably works but I would suggest to add a default constructor with initialization of myVariable.

// untested
struct MyStruct
{
  decimal<2> myVariable;
  MyStruct(): myVariable(0) { }
}

See rules (I have already a headache after reading it):

• https://en.cppreference.com/w/cpp/language/default_initialization
• https://en.cppreference.com/w/cpp/language/rule_of_three
• https://en.cppreference.com/w/cpp/language/aggregate_initialization
• https://isocpp.org/wiki/faq/cpp11-language#uniform-init
• https://en.cppreference.com/w/c/language/struct_initialization

[omerbrandis]

thanks !