• Open Menu Close Menu
  • Apple
  • Shopping Bag
  • Apple
  • Mac
  • iPad
  • iPhone
  • Watch
  • TV
  • Music
  • Support
  • Search apple.com
  • Shopping Bag

Lists

Open Menu Close Menu
  • Terms and Conditions
  • Lists hosted on this site
  • Email the Postmaster
  • Tips for posting to public mailing lists
Re: STL set inside inside a class
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: STL set inside inside a class


  • Subject: Re: STL set inside inside a class
  • From: Paul Forgey <email@hidden>
  • Date: Wed, 17 May 2006 16:43:48 -0700


On May 17, 2006, at 4:10 PM, Jan Brittenson wrote:

Paul Forgey wrote:

That means depthCount[depth]++ will always do what you expect since the default instantiation of a simple scaler type is 0.

This is only true for statics.

In an STL container the behavior is defined. When a std::map inserts an element and the mapped_type of the value to insert is not specified, mapped_type () is used. The constructor instantiation of a simple scaler type is defined to be 0.


e.g.

int i; // undefined
int j = int (); // is 0.


If
the object is static, then its initializer may not have been called yet while some other static
object's initializer wants to call it; in this case review the link order, or the order in which
the static objects appear if they're in the same file.

My experience with any static object having a constructor is to just don't do it.



_______________________________________________ Do not post admin requests to the list. They will be ignored. Xcode-users mailing list (email@hidden) Help/Unsubscribe/Update your Subscription: This email sent to email@hidden
  • Follow-Ups:
    • Re: STL set inside inside a class
      • From: Jan Brittenson <email@hidden>
    • [OT]Static Objects (was Re: STL set inside inside a class)
      • From: "Duane Murphy" <email@hidden>
References: 
 >STL set inside inside a class (From: mark <email@hidden>)
 >Re: STL set inside inside a class (From: Paul Forgey <email@hidden>)
 >Re: STL set inside inside a class (From: Jan Brittenson <email@hidden>)

  • Prev by Date: Re: STL set inside inside a class
  • Next by Date: [OT]Static Objects (was Re: STL set inside inside a class)
  • Previous by thread: Re: STL set inside inside a class
  • Next by thread: [OT]Static Objects (was Re: STL set inside inside a class)
  • Index(es):
    • Date
    • Thread