error with C const string declaration

Question

const char* const back_slash = "\\";
const char* const open_braces ="[";

const char* const array[][2] = {

   {
     back_slash,
    open_braces,

    },
};

In this case i am getting

error: initializer element is not constant

Can you please help?

Please have a look on answers given [Here](http://stackoverflow.com/questions/3025050/error-initializer-element-is-not-constant-when-trying-to-initialize-variable-w). — Dayal rai, Mar 07 '14 at 07:23

score 3 · Answer 1 · edited Mar 07 '14 at 07:25

3

In section 6.7.8/4:

All the expressions in an initializer for an object that has static storage duration shall be constant expressions or string literals.

In the C language, the term "constant" refers to literal constants (like 1, 'a', "[" and so on). back_slash and open_braces are not compile-time constants.

edited Mar 07 '14 at 07:25

Lundin

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answered Mar 07 '14 at 07:20

Sadique

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score 0 · Answer 2 · answered Mar 07 '14 at 07:20

0

An array initializer needs to be a comma-separated list of constant expressions; you are using variables.

answered Mar 07 '14 at 07:20

score 0 · Answer 3 · answered Mar 07 '14 at 07:39

0

These are const-qualified variables for C, so just variables and not constants in the context of initialization. Use defines to name such literals:

#define back_slash "\\"
#define open_braces "["

answered Mar 07 '14 at 07:39

Jens Gustedt

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score 0 · Answer 4 · answered Mar 07 '14 at 07:47

You tried to be too pedantic: C doesn't have real compile time const declarations (with types). One way, to do get the const array part to compile is to declare backslash and open bracket (bracket '[', brace '{') with a #define, unless of course you need them somewhere else. Note about const declarations: one would expect that after 'const int i = 5', i could be used in the code freely and would not appear in the object file. It does, and this can bite you on a small embedded system.

error with C const string declaration

4 Answers4