How to specify the field we wanna use from a struct?
-2
I have a struct composed of multiple fields of same type.
type test struct{
A int
B int
C int
}
I want to apply a function that does the same things to the three fields, but I only wanna do it on one each time.
function something (toto test, cond int) {
if (cond == 1){
// then we will use A for the rest of the function
}else if (cond == 2) {
// then we use B etc....
} ...
for mail, v := range bdd {
if _, ok := someMap[v.A]; !ok { // use v.A or V.B or V.C
delete(bdd, mail)
}
...
}
...
}
The function is really long and I it bothers me to have the code duplicated like 3 times just for one line that changes.
I tried things with the reflect package. I think it's a dangerous idea to go into that.
go struct field reflect
asked Nov 23 '18 at 14:25
DylanDylan
306
add a comment |
-2
I have a struct composed of multiple fields of same type.
type test struct{
A int
B int
C int
}
I want to apply a function that does the same things to the three fields, but I only wanna do it on one each time.
function something (toto test, cond int) {
if (cond == 1){
// then we will use A for the rest of the function
}else if (cond == 2) {
// then we use B etc....
} ...
for mail, v := range bdd {
if _, ok := someMap[v.A]; !ok { // use v.A or V.B or V.C
delete(bdd, mail)
}
...
}
...
}
The function is really long and I it bothers me to have the code duplicated like 3 times just for one line that changes.
I tried things with the reflect package. I think it's a dangerous idea to go into that.
go struct field reflect
asked Nov 23 '18 at 14:25
DylanDylan
306
2
Are you sure you should be storing that information as struct fields? Perhaps a map would be more suitable.
– Tim Cooper
Nov 23 '18 at 14:26
@TimCooper Actually i'm using something like a map[email]test so test contains informations related to that email and i have more than 3 fields actually Making one map per fields is a bit too much and not practical I think
– Dylan
Nov 23 '18 at 14:28
2
If you don't want to use reflection you could make the function variadic taking pointers to the fields. e.gsomething(&t.A, &t.B, &t.C)
– mkopriva
Nov 23 '18 at 15:49
add a comment |
-2
-2
-2
I have a struct composed of multiple fields of same type.
type test struct{
A int
B int
C int
}
I want to apply a function that does the same things to the three fields, but I only wanna do it on one each time.
function something (toto test, cond int) {
if (cond == 1){
// then we will use A for the rest of the function
}else if (cond == 2) {
// then we use B etc....
} ...
for mail, v := range bdd {
if _, ok := someMap[v.A]; !ok { // use v.A or V.B or V.C
delete(bdd, mail)
}
...
}
...
}
The function is really long and I it bothers me to have the code duplicated like 3 times just for one line that changes.
I tried things with the reflect package. I think it's a dangerous idea to go into that.
go struct field reflect
asked Nov 23 '18 at 14:25
DylanDylan
306
I have a struct composed of multiple fields of same type.
type test struct{
A int
B int
C int
}
I want to apply a function that does the same things to the three fields, but I only wanna do it on one each time.
function something (toto test, cond int) {
if (cond == 1){
// then we will use A for the rest of the function
}else if (cond == 2) {
// then we use B etc....
} ...
for mail, v := range bdd {
if _, ok := someMap[v.A]; !ok { // use v.A or V.B or V.C
delete(bdd, mail)
}
...
}
...
}
The function is really long and I it bothers me to have the code duplicated like 3 times just for one line that changes.
I tried things with the reflect package. I think it's a dangerous idea to go into that.
go struct field reflect
go struct field reflect
asked Nov 23 '18 at 14:25
DylanDylan
306
asked Nov 23 '18 at 14:25
DylanDylan
306
edited Nov 23 '18 at 14:38
Dylan
asked Nov 23 '18 at 14:25
DylanDylan
306
asked Nov 23 '18 at 14:25
DylanDylan
306
asked Nov 23 '18 at 14:25
DylanDylan
306
306
2
Are you sure you should be storing that information as struct fields? Perhaps a map would be more suitable.
– Tim Cooper
Nov 23 '18 at 14:26
@TimCooper Actually i'm using something like a map[email]test so test contains informations related to that email and i have more than 3 fields actually Making one map per fields is a bit too much and not practical I think
– Dylan
Nov 23 '18 at 14:28
2
If you don't want to use reflection you could make the function variadic taking pointers to the fields. e.gsomething(&t.A, &t.B, &t.C)
– mkopriva
Nov 23 '18 at 15:49
add a comment |
2
Are you sure you should be storing that information as struct fields? Perhaps a map would be more suitable.
– Tim Cooper
Nov 23 '18 at 14:26
@TimCooper Actually i'm using something like a map[email]test so test contains informations related to that email and i have more than 3 fields actually Making one map per fields is a bit too much and not practical I think
– Dylan
Nov 23 '18 at 14:28
2
If you don't want to use reflection you could make the function variadic taking pointers to the fields. e.gsomething(&t.A, &t.B, &t.C)
– mkopriva
Nov 23 '18 at 15:49
2
2
Are you sure you should be storing that information as struct fields? Perhaps a map would be more suitable.
– Tim Cooper
Nov 23 '18 at 14:26
Are you sure you should be storing that information as struct fields? Perhaps a map would be more suitable.
– Tim Cooper
Nov 23 '18 at 14:26
@TimCooper Actually i'm using something like a map[email]test so test contains informations related to that email and i have more than 3 fields actually Making one map per fields is a bit too much and not practical I think
– Dylan
Nov 23 '18 at 14:28
@TimCooper Actually i'm using something like a map[email]test so test contains informations related to that email and i have more than 3 fields actually Making one map per fields is a bit too much and not practical I think
– Dylan
Nov 23 '18 at 14:28
2
2
If you don't want to use reflection you could make the function variadic taking pointers to the fields. e.g
something(&t.A, &t.B, &t.C)– mkopriva
Nov 23 '18 at 15:49
If you don't want to use reflection you could make the function variadic taking pointers to the fields. e.g
something(&t.A, &t.B, &t.C)– mkopriva
Nov 23 '18 at 15:49
add a comment |
1 Answer
1
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In your situation I'd use map instead of struct, but if struct is really required you can use reflect package.
v := reflect.ValueOf(x)
for i := 0; i < v.NumField(); i++ {
fmt.Printf("%v", v.Field(i).Interface())
}
answered Nov 23 '18 at 14:38
Alex PliutauAlex Pliutau
14.3k2490131
Yeah that was what I tried to do, but then I realised that in a for loop, we had to call reflect for each iteration. I wanted to set the field I wanna use, just once, at the beginning of the function.
– Dylan
Nov 23 '18 at 14:48
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
0
In your situation I'd use map instead of struct, but if struct is really required you can use reflect package.
v := reflect.ValueOf(x)
for i := 0; i < v.NumField(); i++ {
fmt.Printf("%v", v.Field(i).Interface())
}
answered Nov 23 '18 at 14:38
Alex PliutauAlex Pliutau
14.3k2490131
Yeah that was what I tried to do, but then I realised that in a for loop, we had to call reflect for each iteration. I wanted to set the field I wanna use, just once, at the beginning of the function.
– Dylan
Nov 23 '18 at 14:48
add a comment |
0
In your situation I'd use map instead of struct, but if struct is really required you can use reflect package.
v := reflect.ValueOf(x)
for i := 0; i < v.NumField(); i++ {
fmt.Printf("%v", v.Field(i).Interface())
}
answered Nov 23 '18 at 14:38
Alex PliutauAlex Pliutau
14.3k2490131
Yeah that was what I tried to do, but then I realised that in a for loop, we had to call reflect for each iteration. I wanted to set the field I wanna use, just once, at the beginning of the function.
– Dylan
Nov 23 '18 at 14:48
add a comment |
0
0
0
In your situation I'd use map instead of struct, but if struct is really required you can use reflect package.
v := reflect.ValueOf(x)
for i := 0; i < v.NumField(); i++ {
fmt.Printf("%v", v.Field(i).Interface())
}
answered Nov 23 '18 at 14:38
Alex PliutauAlex Pliutau
14.3k2490131
In your situation I'd use map instead of struct, but if struct is really required you can use reflect package.
v := reflect.ValueOf(x)
for i := 0; i < v.NumField(); i++ {
fmt.Printf("%v", v.Field(i).Interface())
}
answered Nov 23 '18 at 14:38
Alex PliutauAlex Pliutau
14.3k2490131
answered Nov 23 '18 at 14:38
Alex PliutauAlex Pliutau
14.3k2490131
answered Nov 23 '18 at 14:38
Alex PliutauAlex Pliutau
14.3k2490131
answered Nov 23 '18 at 14:38
Alex PliutauAlex Pliutau
14.3k2490131
14.3k2490131
Yeah that was what I tried to do, but then I realised that in a for loop, we had to call reflect for each iteration. I wanted to set the field I wanna use, just once, at the beginning of the function.
– Dylan
Nov 23 '18 at 14:48
add a comment |
Yeah that was what I tried to do, but then I realised that in a for loop, we had to call reflect for each iteration. I wanted to set the field I wanna use, just once, at the beginning of the function.
– Dylan
Nov 23 '18 at 14:48
Yeah that was what I tried to do, but then I realised that in a for loop, we had to call reflect for each iteration. I wanted to set the field I wanna use, just once, at the beginning of the function.
– Dylan
Nov 23 '18 at 14:48
Yeah that was what I tried to do, but then I realised that in a for loop, we had to call reflect for each iteration. I wanted to set the field I wanna use, just once, at the beginning of the function.
– Dylan
Nov 23 '18 at 14:48
add a comment |
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2
Are you sure you should be storing that information as struct fields? Perhaps a map would be more suitable.
– Tim Cooper
Nov 23 '18 at 14:26
@TimCooper Actually i'm using something like a map[email]test so test contains informations related to that email and i have more than 3 fields actually Making one map per fields is a bit too much and not practical I think
– Dylan
Nov 23 '18 at 14:28
2
If you don't want to use reflection you could make the function variadic taking pointers to the fields. e.g
something(&t.A, &t.B, &t.C)– mkopriva
Nov 23 '18 at 15:49