Databases
StackOverflow2013
Postsdbo
POHow to pass parameters correctly?
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POHow to pass parameters correctly?
    primarykey
    data
    text
    <p>I am a C++ beginner but not a programming beginner. I'm trying to learn C++(c++11) and it's kinda unclear for me the most important thing: passing parameters.</p> <p>I considered these simple examples:</p> <ul> <li><p>A class that has all its members primitive types:<br> <code>CreditCard(std::string number, int expMonth, int expYear,int pin):number(number), expMonth(expMonth), expYear(expYear), pin(pin)</code></p></li> <li><p>A class that has as members primitive types + 1 complex type:<br> <code>Account(std::string number, float amount, CreditCard creditCard) : number(number), amount(amount), creditCard(creditCard)</code></p></li> <li><p>A class that has as members primitive types + 1 collection of some complex type: <code>Client(std::string firstName, std::string lastName, std::vector&lt;Account&gt; accounts):firstName(firstName), lastName(lastName), accounts(accounts)</code></p></li> </ul> <p>When I create an account, I do this: </p> <pre><code> CreditCard cc("12345",2,2015,1001); Account acc("asdasd",345, cc); </code></pre> <p>Obviously the credit card will be copied twice in this scenario. If I rewrite that constructor as</p> <pre><code>Account(std::string number, float amount, CreditCard&amp; creditCard) : number(number) , amount(amount) , creditCard(creditCard) </code></pre> <p>there will be one copy. If I rewrite it as</p> <pre><code>Account(std::string number, float amount, CreditCard&amp;&amp; creditCard) : number(number) , amount(amount) , creditCard(std::forward&lt;CreditCard&gt;(creditCard)) </code></pre> <p>There will be 2 moves and no copy.</p> <p>I think sometimes you may want to copy some parameter, sometimes you don't want to copy when you create that object.<br> I come from C# and, being used to references, it's a bit strange to me and I think there should be 2 overloads for each parameter but I know I am wrong.<br> Are there any best practices of how to send parameters in C++ because I really find it, let's say, not trivial. How would you handle my examples presented above?</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. This table or related slice is empty.
    1. USJack Willson
    plurals
    1. PL
      singulars
      1. LTLinked
    2. PL
      singulars
      1. LTLinked
    1. PL
      singulars
      1. LTLinked
    2. PL
      singulars
      1. LTDuplicate
    3. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POHow to pass parameters correctly?
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. POHow to pass parameters correctly?
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. POHow to pass parameters correctly?
      1. This table or related slice is empty.
      1. VTUpMod
    1. COMeta: I can't believe somebody just asked a good C++ question. +1.
      singulars
      1. POHow to pass parameters correctly?
      1. This table or related slice is empty.
    2. COFYI, `std::string` is a class, just like `CreditCard`, not a primitive type.
      singulars
      1. POHow to pass parameters correctly?
      1. USchris
    3. COWhere is Sir Skeet?
      singulars
      1. POHow to pass parameters correctly?
      1. USchue x
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload