Databases
StackOverflow2013
Postsdbo
POWhat is the member variables list after the colon in a constructor good for?
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POWhat is the member variables list after the colon in a constructor good for?
    primarykey
    data
    text
    <p>I'm reading this C++ open source code and I came to a constructor but I don't get it ( basically because I don't know C++ :P ) </p> <p>I understand C and Java very well.</p> <pre><code> TransparentObject::TransparentObject( int w, int x, int y, int z ) : _someMethod( 0 ), _someOtherMethod( 0 ), _someOtherOtherMethod( 0 ), _someMethodX( 0 ) { int bla; int bla; } </code></pre> <p>As far I can "deduce" The first line only declares the construtor name, the "::" sounds like "belongs to" to me. And the code between {} is the constructor body it self. </p> <p>I "think" what's after the paremeters and the first "{" are like methods default parameters or something, but I don't find a reasonable explanation on the web. Most of the C++ constructors that I found in the examples are almost identical to those in Java.</p> <p>I'm I right in my assumptions? "::" is like belongs to, and the list after params and body are like "default args" or something?</p> <p><strong>UPDATE:</strong> Thanks for the answers. May those be called methods? ( I guess no ) and what is the difference of call them within the constructor body</p>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USfredoverflow
    1. USOscarRyz
    plurals
    1. PL
      singulars
      1. LTLinked
    1. PL
      singulars
      1. LTLinked
    2. PL
      singulars
      1. LTLinked
    3. PL
      singulars
      1. LTDuplicate
    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. POWhat is the member variables list after the colon in a constructor good for?
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. POWhat is the member variables list after the colon in a constructor good for?
      1. This table or related slice is empty.
      1. VTDownMod
    3. VO
      singulars
      1. POWhat is the member variables list after the colon in a constructor good for?
      1. This table or related slice is empty.
      1. VTUpMod
    1. COInitialising them in the list is preffered - it's the only way to init const variables, it guarrantees the order (if that matters) and is more efficent.
      singulars
      1. POWhat is the member variables list after the colon in a constructor good for?
      1. USMartin Beckett
    2. CO@mgb - it should also be noted that it's the only way to initialize references too.
      singulars
      1. POWhat is the member variables list after the colon in a constructor good for?
      1. USJason Baker
    3. COAnd the initialization happens right before the control is transfered to the constructor body.
      singulars
      1. POWhat is the member variables list after the colon in a constructor good for?
      1. USLeonardo Constantino
 

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