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Offline (Male) RetroX
Reply #15 Posted on: March 05, 2010, 09:37:59 PM

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That's const char*

char* would mean something like this:
Code: [Select]
char x[]={'h','e','l','l','o',',',' ','\0'};
char y[]={'d','a','m','n','i','t','\0'};
char *z=x+y;
or
Code: [Select]
char *z=const_cast<char*>("hello, ")+const_cast<char*>("damnit");
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Offline (Male) Josh @ Dreamland
Reply #16 Posted on: March 05, 2010, 09:54:21 PM

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The only difference between const char* and char* is that const char* points to read-only memory. And even that's only on systems that support such (ie, not Windows). '\0' == 0, and I'd be willing to bet that if you were to compare {'n','o',0} and "no" you'd get that they were equivalent. And I do mean as-is.

"Test" == "test" compares correctly for string literals. "Test" == "test" will return false, "test" == "test" will return true. This is because they point to the same location in memory when GCC is done with them.

Also, you don't need to use const_cast to get it represented as a const char. :P
Const char* can be set to a char* without cast. Vice-versa requires cast, but is dangerous on Linux and the like.
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Offline (Male) RetroX
Reply #17 Posted on: March 05, 2010, 10:04:53 PM

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The only difference between const char* and char* is that const char* points to read-only memory. And even that's only on systems that support such (ie, not Windows). '\0' == 0, and I'd be willing to bet that if you were to compare {'n','o',0} and "no" you'd get that they were equivalent. And I do mean as-is.

"Test" == "test" compares correctly for string literals. "Test" == "test" will return false, "test" == "test" will return true. This is because they point to the same location in memory when GCC is done with them.

Also, you don't need to use const_cast to get it represented as a const char. :P
Const char* can be set to a char* without cast. Vice-versa requires cast, but is dangerous on Linux and the like.
Whenever I have tried to do it without const_cast, G++ bugs me about a depreciated conversion (that works).  I always use -Wall and purge all warnings and errors, and that is one that I happen to get into the habit of doing.
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Offline (Unknown gender) score_under
Reply #18 Posted on: March 06, 2010, 08:59:16 AM

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That's const char*

char* would mean something like this:
Code: [Select]
char x[]={'h','e','l','l','o',',',' ','\0'};
char y[]={'d','a','m','n','i','t','\0'};
char *z=x+y;
or
Code: [Select]
char *z=const_cast<char*>("hello, ")+const_cast<char*>("damnit");
Wait, what?
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Offline (Male) RetroX
Reply #19 Posted on: March 06, 2010, 03:25:17 PM

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That's const char*

char* would mean something like this:
Code: [Select]
char x[]={'h','e','l','l','o',',',' ','\0'};
char y[]={'d','a','m','n','i','t','\0'};
char *z=x+y;
or
Code: [Select]
char *z=const_cast<char*>("hello, ")+const_cast<char*>("damnit");
Wait, what?
Exactly.  It's pointless.
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Why do all the pro-Microsoft people have troll avatars? :(
Offline (Unknown gender) score_under
Reply #20 Posted on: March 06, 2010, 08:30:41 PM

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That's const char*

char* would mean something like this:
Code: [Select]
char x[]={'h','e','l','l','o',',',' ','\0'};
char y[]={'d','a','m','n','i','t','\0'};
char *z=x+y;
or
Code: [Select]
char *z=const_cast<char*>("hello, ")+const_cast<char*>("damnit");
Wait, what?
Exactly.  It's pointless.
Tell me...
Code: [Select]
char x[]={'h','e','l','l','o',',',' ','\0'};
char y[]={'d','a','m','n','i','t','\0'};
char *z=x+y;
printf("%c",z[2]);
...What happens when you run that? If you say "prints l" I'll shoot your face off. If you say "access violation because you added 2 random pointers", then I'll forgive you... for now.
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Offline (Unknown gender) Micah
Reply #21 Posted on: March 06, 2010, 09:45:48 PM

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Of course it's adding two random pointers. He was explaining what I meant when I asked if you could overload operator+ for two char *s.
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Offline (Unknown gender) score_under
Reply #22 Posted on: March 06, 2010, 10:15:45 PM

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I see, though overloading the + for a char* is really pointless IMO.
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Offline (Male) Josh @ Dreamland
Reply #23 Posted on: March 06, 2010, 10:18:28 PM

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Yeah, compiler presently concatenates "" + "" automatically. For "" + anything else, I want it to cast first "" to variant.
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Offline (Male) Rusky
Reply #24 Posted on: March 06, 2010, 11:19:35 PM

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It concatenates "" "" automatically. someCharPtr + "" is what might be useful to overload, to avoid std::string constructor noise. However, I agree that it's not very useful. Allowing operator overloading on arbitrary types would make the language completely unpredictable; it'd be worse than monkeypatching in Ruby.
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