Questions tagged [const-string]
11 questions
7
votes
5 answers
Why strrchr() returns `char*` instead of `const char*`?
The function char* strrchr(const char *str, int ch) returns a pointer (char*) within str (const char *) where the last occurrence of ch is located.
So we can write the following code without any cast:
#include
int main()
{
const char…
oHo
- 51,447
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5
votes
4 answers
is static const string member variable always initialized before used?
In C++, if I want to define some non-local const string which can be used in different classes, functions, files, the approaches that I know are:
use define directives, e.g.
#define STR_VALUE "some_string_value"
const class member variable,…
Hunter
- 151
- 1
- 14
2
votes
0 answers
Memory optimization: declare multiple string variables VS use in place
I have to code a class with heavy memory allocation considerations.
This class have strings all over the place like so
var data = GetPropertyValue(response.BaseData, "scriptData");
Just like "scriptData" there are over 10 strings declared…
UndercoverNoob
- 73
- 6
2
votes
2 answers
User Defined String Literals compared to Const Strings
Consider the following code with these two structures:
std::string operator"" _str(const char* str, std::size_t len) {
return std::string( str, len );
}
struct MessageLiterals {
std::string HELP = "Press F1 for help"_str;
std::string…
Francis Cugler
- 7,788
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2
votes
2 answers
Where does const string store? in stack or .data?
I have written a simple c code which shows below. In this code snippet I want to verify where the const string abcd stores. I first guess that it should be stored in .data section for read-only. After a test in Debian, however, things is different…
Douglas Su
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1
vote
1 answer
const_string lib issue
I'm trying const_string lib that looks not bad, but it crashes at runtime with access violation(atomic_count, operator++()). The test code:
#include
#include
typedef…
G0r
- 13
- 2
1
vote
1 answer
Trouble with passing C string literals to a function while using a C++ compiler to compile the code?
I'm getting an error that says "argument type "const char *" is incompatible with "char *". This code was provided by my professor and I'm not sure what the problem is.
I'm writing C but I'm using a C++ compiler because it is easier to debug if…
Destin Hilt
- 15
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1
vote
1 answer
Why segmentation fault happened when i define a const string in a google test programe?
I want to run unit test with google test, but got Segmentation fault. I have just define a global const string, and RUN_ALL_TESTS, why?
the gdb result is :
[Thread debugging using libthread_db enabled]
Using host libthread_db library…
BalrogMithrandir
- 21
- 2
0
votes
1 answer
const_string as map key; make a buffer copy?
the whole point of const_string is avoiding make a unnecesary copy when the string is not supposed to change.
However, there are circumstances where you cannot guarantee the lifetime of the const char* source to outlive the const_string, for…
lurscher
- 25,930
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0
votes
2 answers
How to compare a string to a const string in C++
Let's say I have the following poc code:
const string& a = "hello";
string b = "l";
if(a.at(2) == b)
{
// do stuff
}
I understand that there is no operator "==" that matches these operands. And, the way to fix it is by converting the value of…
Xigma
- 177
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-2
votes
1 answer
What is the best way to declare "string" variables in C #?
I'm a new developer and I have two questions, I researched and it wasn't very clear to me.
What is the difference between using a "string" variable to "String"?
what is the difference between the two examples below
string my_example = "title…
Thiago Alexandre
- 21
- 5