Dart indexWhere performance
I want to search index where fb3 is.
I have two options indexA and indexB like so.
Is there any performance differences like A is faster than B or vice versa?
Is there any better way to search fb3?
class Foo {
String id; //unique
int number;
Foo(this.id, this.number);
}
class Bar {
String id; //unique
int number;
Bar(this.id, this.number);
}
class FooBar {
Foo foo;
Bar bar;
FooBar(this.foo, this.bar);
}
void main() {
final Foo f = Foo('First Id', 18);
final Bar b = Bar('Second Id', 81);
final FooBar fb = FooBar(f, b);
final Foo f2 = Foo('Third Id', 900);
final Bar b2 = Bar('Fourth Id', 009);
final FooBar fb2 = FooBar(f2, b2);
final Foo f3 = Foo('Fifth Id', 789);
final Bar b3 = Bar('Sixth Id', 987);
final FooBar fb3 = FooBar(f3, b3);
final Foo f4 = Foo('Seventh Id', 222);
final Bar b4 = Bar('Eighth Id', 666);
final FooBar fb4 = FooBar(f4, b4);
final List<FooBar> fbs = [fb, fb2, fb3, fb4];
final int indexA = fbs.indexWhere((FooBar fb) => fb.foo.id == fb3.foo.id && fb.bar.id == fb3.bar.id);
final int indexB = fbs.indexWhere((FooBar fb) => fb == fb3);
}
dart asked Nov 13 '18 at 1:22
TwoSanTwoSan
246111
add a comment |
I want to search index where fb3 is.
I have two options indexA and indexB like so.
Is there any performance differences like A is faster than B or vice versa?
Is there any better way to search fb3?
class Foo {
String id; //unique
int number;
Foo(this.id, this.number);
}
class Bar {
String id; //unique
int number;
Bar(this.id, this.number);
}
class FooBar {
Foo foo;
Bar bar;
FooBar(this.foo, this.bar);
}
void main() {
final Foo f = Foo('First Id', 18);
final Bar b = Bar('Second Id', 81);
final FooBar fb = FooBar(f, b);
final Foo f2 = Foo('Third Id', 900);
final Bar b2 = Bar('Fourth Id', 009);
final FooBar fb2 = FooBar(f2, b2);
final Foo f3 = Foo('Fifth Id', 789);
final Bar b3 = Bar('Sixth Id', 987);
final FooBar fb3 = FooBar(f3, b3);
final Foo f4 = Foo('Seventh Id', 222);
final Bar b4 = Bar('Eighth Id', 666);
final FooBar fb4 = FooBar(f4, b4);
final List<FooBar> fbs = [fb, fb2, fb3, fb4];
final int indexA = fbs.indexWhere((FooBar fb) => fb.foo.id == fb3.foo.id && fb.bar.id == fb3.bar.id);
final int indexB = fbs.indexWhere((FooBar fb) => fb == fb3);
}
asked Nov 13 '18 at 1:22
TwoSanTwoSan
246111
add a comment |
I want to search index where fb3 is.
I have two options indexA and indexB like so.
Is there any performance differences like A is faster than B or vice versa?
Is there any better way to search fb3?
class Foo {
String id; //unique
int number;
Foo(this.id, this.number);
}
class Bar {
String id; //unique
int number;
Bar(this.id, this.number);
}
class FooBar {
Foo foo;
Bar bar;
FooBar(this.foo, this.bar);
}
void main() {
final Foo f = Foo('First Id', 18);
final Bar b = Bar('Second Id', 81);
final FooBar fb = FooBar(f, b);
final Foo f2 = Foo('Third Id', 900);
final Bar b2 = Bar('Fourth Id', 009);
final FooBar fb2 = FooBar(f2, b2);
final Foo f3 = Foo('Fifth Id', 789);
final Bar b3 = Bar('Sixth Id', 987);
final FooBar fb3 = FooBar(f3, b3);
final Foo f4 = Foo('Seventh Id', 222);
final Bar b4 = Bar('Eighth Id', 666);
final FooBar fb4 = FooBar(f4, b4);
final List<FooBar> fbs = [fb, fb2, fb3, fb4];
final int indexA = fbs.indexWhere((FooBar fb) => fb.foo.id == fb3.foo.id && fb.bar.id == fb3.bar.id);
final int indexB = fbs.indexWhere((FooBar fb) => fb == fb3);
}
asked Nov 13 '18 at 1:22
TwoSanTwoSan
246111
I want to search index where fb3 is.
I have two options indexA and indexB like so.
Is there any performance differences like A is faster than B or vice versa?
Is there any better way to search fb3?
class Foo {
String id; //unique
int number;
Foo(this.id, this.number);
}
class Bar {
String id; //unique
int number;
Bar(this.id, this.number);
}
class FooBar {
Foo foo;
Bar bar;
FooBar(this.foo, this.bar);
}
void main() {
final Foo f = Foo('First Id', 18);
final Bar b = Bar('Second Id', 81);
final FooBar fb = FooBar(f, b);
final Foo f2 = Foo('Third Id', 900);
final Bar b2 = Bar('Fourth Id', 009);
final FooBar fb2 = FooBar(f2, b2);
final Foo f3 = Foo('Fifth Id', 789);
final Bar b3 = Bar('Sixth Id', 987);
final FooBar fb3 = FooBar(f3, b3);
final Foo f4 = Foo('Seventh Id', 222);
final Bar b4 = Bar('Eighth Id', 666);
final FooBar fb4 = FooBar(f4, b4);
final List<FooBar> fbs = [fb, fb2, fb3, fb4];
final int indexA = fbs.indexWhere((FooBar fb) => fb.foo.id == fb3.foo.id && fb.bar.id == fb3.bar.id);
final int indexB = fbs.indexWhere((FooBar fb) => fb == fb3);
}
asked Nov 13 '18 at 1:22
TwoSanTwoSan
246111
asked Nov 13 '18 at 1:22
TwoSanTwoSan
246111
asked Nov 13 '18 at 1:22
TwoSanTwoSan
246111
asked Nov 13 '18 at 1:22
TwoSanTwoSan
246111
asked Nov 13 '18 at 1:22
TwoSanTwoSan
246111
246111
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
If Foo, Bar, and FooBar do not implement operator== and get hashCode then indexB will only find identical instances.
var a = Foo('Fifth Id', 789);
var b = Foo('Fifth Id', 789);
var c = a;
print(a == b); // false
print(a == c); // true
See also How does a set determine that two objects are equal in dart?
There won't be any performance difference worth mentioning if operator == is implemented. If you actually only want to find identicial instances then indexB would be faster, but then it would be better to use
(FooBar fb) => identical(fb, fb3)
answered Nov 13 '18 at 6:48
Günter ZöchbauerGünter Zöchbauer
316k66935881
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
If Foo, Bar, and FooBar do not implement operator== and get hashCode then indexB will only find identical instances.
var a = Foo('Fifth Id', 789);
var b = Foo('Fifth Id', 789);
var c = a;
print(a == b); // false
print(a == c); // true
See also How does a set determine that two objects are equal in dart?
There won't be any performance difference worth mentioning if operator == is implemented. If you actually only want to find identicial instances then indexB would be faster, but then it would be better to use
(FooBar fb) => identical(fb, fb3)
answered Nov 13 '18 at 6:48
Günter ZöchbauerGünter Zöchbauer
316k66935881
add a comment |
If Foo, Bar, and FooBar do not implement operator== and get hashCode then indexB will only find identical instances.
var a = Foo('Fifth Id', 789);
var b = Foo('Fifth Id', 789);
var c = a;
print(a == b); // false
print(a == c); // true
See also How does a set determine that two objects are equal in dart?
There won't be any performance difference worth mentioning if operator == is implemented. If you actually only want to find identicial instances then indexB would be faster, but then it would be better to use
(FooBar fb) => identical(fb, fb3)
answered Nov 13 '18 at 6:48
Günter ZöchbauerGünter Zöchbauer
316k66935881
add a comment |
If Foo, Bar, and FooBar do not implement operator== and get hashCode then indexB will only find identical instances.
var a = Foo('Fifth Id', 789);
var b = Foo('Fifth Id', 789);
var c = a;
print(a == b); // false
print(a == c); // true
See also How does a set determine that two objects are equal in dart?
There won't be any performance difference worth mentioning if operator == is implemented. If you actually only want to find identicial instances then indexB would be faster, but then it would be better to use
(FooBar fb) => identical(fb, fb3)
answered Nov 13 '18 at 6:48
Günter ZöchbauerGünter Zöchbauer
316k66935881
If Foo, Bar, and FooBar do not implement operator== and get hashCode then indexB will only find identical instances.
var a = Foo('Fifth Id', 789);
var b = Foo('Fifth Id', 789);
var c = a;
print(a == b); // false
print(a == c); // true
See also How does a set determine that two objects are equal in dart?
There won't be any performance difference worth mentioning if operator == is implemented. If you actually only want to find identicial instances then indexB would be faster, but then it would be better to use
(FooBar fb) => identical(fb, fb3)
answered Nov 13 '18 at 6:48
Günter ZöchbauerGünter Zöchbauer
316k66935881
answered Nov 13 '18 at 6:48
Günter ZöchbauerGünter Zöchbauer
316k66935881
answered Nov 13 '18 at 6:48
Günter ZöchbauerGünter Zöchbauer
316k66935881
answered Nov 13 '18 at 6:48
Günter ZöchbauerGünter Zöchbauer
316k66935881
316k66935881
add a comment |
add a comment |
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