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Re: Why does this work on Xcode ???

Subject Re: Why does this work on Xcode ???
Newsgroups comp.lang.c++
References <1b10612f-47b9-4097-be59-d00dec4a800b@googlegroups.com> <qgnd93$tap$1@dont-email.me>
From Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk>
Organization Jupiter Mining Corporation
Message-ID <odMXE.11583$0A3.11258@fx21.fr7> (permalink)
Date 2019-07-17 22:15 +0100

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On 17/07/2019 16:01, Alf P. Steinbach wrote:
> On 17.07.2019 07:03, Bob Langelaan wrote:
>> Several of my students have submitted the following solution (or
>> something very similar) for a recursive function to add the contents
>> of an array:
> 
> The presented code doesn't “add the contents”, I guess that's just typo.
> 
> 
>> // Returns true if the supplied value is found in the array of values
>> // and false otherwise
>> template <typename type, size_t size>
>> bool isMember(const array<type,size> & myArray, const int n, const type 
>> value)
>> {
>>     if ( n < 0 )
>>     {
>>         return false;
>>     }
>>     else if ( myArray[n] == value )
>>     {
>>         return true;
>>     }
>>     return isMember( myArray, n - 1, value );
>> }
> 
> The two main problems with this function are:
> 
> * Passing `value` by value may incur severe copying inefficiency.
> * The tail recursion may easily consume all stack space and yield UB.

The whole point of using tail recursion is that is doesn't use up stack 
space, silly boy.

/Flibble

-- 
"Snakes didn't evolve, instead talking snakes with legs changed into 
snakes." - Rick C. Hodgin

“You won’t burn in hell. But be nice anyway.” – Ricky Gervais

“I see Atheists are fighting and killing each other again, over who 
doesn’t believe in any God the most. Oh, no..wait.. that never happens.” – 
Ricky Gervais

"Suppose it's all true, and you walk up to the pearly gates, and are 
confronted by God," Bryne asked on his show The Meaning of Life. "What 
will Stephen Fry say to him, her, or it?"
"I'd say, bone cancer in children? What's that about?" Fry replied.
"How dare you? How dare you create a world to which there is such misery 
that is not our fault. It's not right, it's utterly, utterly evil."
"Why should I respect a capricious, mean-minded, stupid God who creates a 
world that is so full of injustice and pain. That's what I would say."

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Thread

Why does this work on Xcode ??? Bob Langelaan <bobl0456@gmail.com> - 2019-07-16 22:03 -0700
  Re: Why does this work on Xcode ??? Paavo Helde <myfirstname@osa.pri.ee> - 2019-07-17 08:46 +0300
  Re: Why does this work on Xcode ??? Öö Tiib <ootiib@hot.ee> - 2019-07-17 00:06 -0700
    Re: Why does this work on Xcode ??? Öö Tiib <ootiib@hot.ee> - 2019-07-17 01:44 -0700
  Re: Why does this work on Xcode ??? Juha Nieminen <nospam@thanks.invalid> - 2019-07-17 07:46 +0000
  Re: Why does this work on Xcode ??? James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-07-17 09:12 -0400
  Re: Why does this work on Xcode ??? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-07-17 17:01 +0200
    Re: Why does this work on Xcode ??? Mr Flibble <flibbleREMOVETHISBIT@i42.co.uk> - 2019-07-17 22:15 +0100
      Re: Why does this work on Xcode ??? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-07-17 23:29 +0200
        Re: Why does this work on Xcode ??? Christian Gollwitzer <auriocus@gmx.de> - 2019-07-19 08:27 +0200
          Re: Why does this work on Xcode ??? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-07-19 09:09 +0200
            Re: Why does this work on Xcode ??? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-07-19 09:24 +0200
            Re: Why does this work on Xcode ??? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-08-10 11:18 -0700
              Re: Why does this work on Xcode ??? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-08-10 21:05 +0200
                Re: Why does this work on Xcode ??? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-08-22 10:28 -0700
                Re: Why does this work on Xcode ??? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-08-22 19:50 +0200
                Re: Why does this work on Xcode ??? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-08-22 23:45 +0100
                Re: Why does this work on Xcode ??? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-08-23 07:22 +0200
                Re: Why does this work on Xcode ??? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-08-23 13:12 +0100
                Re: Why does this work on Xcode ??? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-08-23 16:02 +0200
                Re: Why does this work on Xcode ??? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-09-18 08:50 -0700
                Re: Why does this work on Xcode ??? James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-08-23 09:28 -0400
                Re: Why does this work on Xcode ??? David Brown <david.brown@hesbynett.no> - 2019-08-23 16:37 +0200
                Re: Why does this work on Xcode ??? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-08-23 23:07 +0200
                Re: Why does this work on Xcode ??? Richard Damon <Richard@Damon-Family.org> - 2019-08-23 19:10 -0400
                Re: Why does this work on Xcode ??? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-08-24 06:49 +0200
                Re: Why does this work on Xcode ??? James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-08-23 19:49 -0400
                Re: Why does this work on Xcode ??? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-08-24 06:45 +0200
                Re: Why does this work on Xcode ??? David Brown <david.brown@hesbynett.no> - 2019-08-25 12:06 +0200
                Re: Why does this work on Xcode ??? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-08-25 13:25 +0200
                Re: Why does this work on Xcode ??? David Brown <david.brown@hesbynett.no> - 2019-08-25 15:11 +0200
                Re: Why does this work on Xcode ??? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-08-25 17:12 +0200
                Re: Why does this work on Xcode ??? David Brown <david.brown@hesbynett.no> - 2019-08-25 23:32 +0200
                Re: Why does this work on Xcode ??? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-08-26 11:51 +0200
                Re: Why does this work on Xcode ??? David Brown <david.brown@hesbynett.no> - 2019-08-26 13:26 +0200
                Re: Why does this work on Xcode ??? David Brown <david.brown@hesbynett.no> - 2019-08-25 11:36 +0200
                Re: Why does this work on Xcode ??? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2019-08-25 13:27 +0200
                Re: Why does this work on Xcode ??? David Brown <david.brown@hesbynett.no> - 2019-08-25 15:15 +0200
                Re: Why does this work on Xcode ??? James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-08-26 00:43 -0400
                Re: Why does this work on Xcode ??? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-08-24 04:58 -0700
                Re: Why does this work on Xcode ??? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-08-26 09:53 -0700
                Re: Why does this work on Xcode ??? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-08-28 18:03 -0700
          Re: Why does this work on Xcode ??? Öö Tiib <ootiib@hot.ee> - 2019-07-19 00:20 -0700
          Re: Why does this work on Xcode ??? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-08-09 07:41 -0700
      Re: Why does this work on Xcode ??? Bonita Montero <Bonita.Montero@gmail.com> - 2019-08-24 19:49 +0200
    Re: Why does this work on Xcode ??? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2019-07-21 11:41 +0000
      Re: Why does this work on Xcode ??? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2019-08-10 09:29 -0700

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