String Table

A table of string pointers lets one index select a message.

pointer table An array of `const char *` values stores addresses of string literals.

selected string Changing an index chooses a different string without copying text.

                            index
                            index = 1 (default)index = 0index = 2
                        

                            string_table.c
                        
Replay: real traced execution (multi-file project)

                            #include <stdio.h>

int main(void) {
    int index = 1;
    const char *names[3] = {"red", "green", "blue"};
    const char *selected = names[index];

    printf("name=%s\n", selected);
    return 0;
}
#include <stdio.h>

int main(void) {
    int index = 0;
    const char *names[3] = {"red", "green", "blue"};
    const char *selected = names[index];

    printf("name=%s\n", selected);
    return 0;
}
#include <stdio.h>

int main(void) {
    int index = 2;
    const char *names[3] = {"red", "green", "blue"};
    const char *selected = names[index];

    printf("name=%s\n", selected);
    return 0;
}

                        
1index ← 1, names ← ⟨addr A⟩, selected ← green⋯3int main(void) {4    int index→ 1 = 1; //@index=0, 25    const char *names→ ⟨addr A⟩[3] = {"red", "green", "blue"};6    const char *selected→ green = names[index]green;78    printf("name=%s\n", selectedgreen);9    return 0;10}⋯outputname=green
1index ← 0, names ← ⟨addr A⟩, selected ← red⋯3int main(void) {4    int index→ 0 = 0;5    const char *names→ ⟨addr A⟩[3] = {"red", "green", "blue"};6    const char *selected→ red = names[index]red;78    printf("name=%s\n", selectedred);9    return 0;10}⋯outputname=red
1index ← 2, names ← ⟨addr A⟩, selected ← blue⋯3int main(void) {4    int index→ 2 = 2;5    const char *names→ ⟨addr A⟩[3] = {"red", "green", "blue"};6    const char *selected→ blue = names[index]blue;78    printf("name=%s\n", selectedblue);9    return 0;10}⋯outputname=blue