why initialization in structure is done where object is created please see below code?

Question

struct st {
    int i;
    char ch;
    float f;
};
int main() {
    struct st var = {2, 'h', 33.45}, var2; // here initialization is gud

    var2= {3, 't', 55}; // here initialization is bad why?

    printf("%d %c %f\n", var.i, var.ch, var.f);
    printf("%d %c %f\n", var2.i, var2.ch, var2.f);
}

`var2.i={3,'t',55};` how possible what it indicate from your point of view? look you accessing `int i` now not whole `struct`. it should be `var2`. what exactly you want? need to learn more about `c` for initialization and assignment. — Jayesh Bhoi, Aug 25 '14 at 04:53
I assume you mean `var2`, not `var2.i`, then it's a duplicate. — Yu Hao, Aug 25 '14 at 04:57
but you can write this `var2 = (struct st){3, 't', 55};` c99 later. — BLUEPIXY, Aug 25 '14 at 09:05

score 1 · Answer 1 · answered Aug 25 '14 at 04:55

1

After declaration, the below syntax can should be followed to init the structure elements.

    var2.i=2;
    var2.ch='t';
    var2.f=55;

This is the syntax of C language.

answered Aug 25 '14 at 04:55

mahendiran.b

1,315
7
13

ok suppose ch[10] is declare in above structure then why var2.ch="hello"; is not possible? – rost rost Aug 25 '14 at 06:38
@rostrost, no var2.ch="hello"; is not possible if ch is array. suppose ch is char*ch then var2.ch="hello"; is possible. – mahendiran.b Aug 25 '14 at 06:42
thanks can u please explain why? – rost rost Aug 25 '14 at 06:45

cppcoder · Answer 2 · 2014-08-25T05:03:18.780

0

It should be

struct st var2 = {3,'t',55};

or

struct st var2;
var2.i = 3;
var2.ch = 't';
var2.f = 55;

edited Aug 25 '14 at 05:03

answered Aug 25 '14 at 04:55

cppcoder

22,227
6
56
81

2

Wrong, if it were assignment, `var2 = {3,'t',55};` doesn't compile. See the duplicate question. – Yu Hao Aug 25 '14 at 04:59
@YuHao please can u say why its not possible? – rost rost Aug 25 '14 at 05:15
@rostrost See the duplicate question. 1. it's assignment, not initialization 2. C doesn't allow this syntax in assignment. – Yu Hao Aug 25 '14 at 05:18
@YuHao s1.str="Hello"; is assignment. You can initialize a char array to a string literal, but not through assignment. can u please explain why its not possible with assignment? – rost rost Aug 25 '14 at 07:04
1

@rostrost Because C doesn't allow it. – Yu Hao Aug 25 '14 at 07:06
@YuHao ya i got it but there must be some technical reason? – rost rost Aug 25 '14 at 07:16

why initialization in structure is done where object is created please see below code?

2 Answers2