Mixing
Why is Polymorphism is needed when we have the keyword “auto” in C++
Correct me if i'm wrong, but the keyword "auto" can solve all the problems that polymorphism was invented to solve.
instead of declaring of virtual function func of class A, when we have Class B inheriting from it, we can just say that the function func is receiving auto param, and it will know what case to trigger.
What do i miss?
c++ oop polymorphism
asked Nov 19 '18 at 16:10
Or251
1829
add a comment |
Correct me if i'm wrong, but the keyword "auto" can solve all the problems that polymorphism was invented to solve.
instead of declaring of virtual function func of class A, when we have Class B inheriting from it, we can just say that the function func is receiving auto param, and it will know what case to trigger.
What do i miss?
c++ oop polymorphism
asked Nov 19 '18 at 16:10
Or251
1829
1
Correct me if i'm wrong, but the keyword "auto" can solve all the problems that polymorphism was invented to solve.You're wrong. Try for examplestd::vector<auto*>
– tkausl
Nov 19 '18 at 16:11
2
You should list the problems that polymorphism (built-in runtime polymorphism in case ofvirtualfunctions being involved) was invented to solve and explain for each problem how it could be solved withauto. Your current "just say that the function func is receiving auto param" makes no sense.
– VTT
Nov 19 '18 at 16:17
add a comment |
Correct me if i'm wrong, but the keyword "auto" can solve all the problems that polymorphism was invented to solve.
instead of declaring of virtual function func of class A, when we have Class B inheriting from it, we can just say that the function func is receiving auto param, and it will know what case to trigger.
What do i miss?
c++ oop polymorphism
asked Nov 19 '18 at 16:10
Or251
1829
Correct me if i'm wrong, but the keyword "auto" can solve all the problems that polymorphism was invented to solve.
instead of declaring of virtual function func of class A, when we have Class B inheriting from it, we can just say that the function func is receiving auto param, and it will know what case to trigger.
What do i miss?
c++ oop polymorphism
c++ oop polymorphism
asked Nov 19 '18 at 16:10
Or251
1829
asked Nov 19 '18 at 16:10
Or251
1829
asked Nov 19 '18 at 16:10
Or251
1829
asked Nov 19 '18 at 16:10
Or251
1829
asked Nov 19 '18 at 16:10
Or251
1829
1829
1
Correct me if i'm wrong, but the keyword "auto" can solve all the problems that polymorphism was invented to solve.You're wrong. Try for examplestd::vector<auto*>
– tkausl
Nov 19 '18 at 16:11
2
You should list the problems that polymorphism (built-in runtime polymorphism in case ofvirtualfunctions being involved) was invented to solve and explain for each problem how it could be solved withauto. Your current "just say that the function func is receiving auto param" makes no sense.
– VTT
Nov 19 '18 at 16:17
add a comment |
1
Correct me if i'm wrong, but the keyword "auto" can solve all the problems that polymorphism was invented to solve.You're wrong. Try for examplestd::vector<auto*>
– tkausl
Nov 19 '18 at 16:11
2
You should list the problems that polymorphism (built-in runtime polymorphism in case ofvirtualfunctions being involved) was invented to solve and explain for each problem how it could be solved withauto. Your current "just say that the function func is receiving auto param" makes no sense.
– VTT
Nov 19 '18 at 16:17
1
1
Correct me if i'm wrong, but the keyword "auto" can solve all the problems that polymorphism was invented to solve. You're wrong. Try for example std::vector<auto*>– tkausl
Nov 19 '18 at 16:11
Correct me if i'm wrong, but the keyword "auto" can solve all the problems that polymorphism was invented to solve. You're wrong. Try for example std::vector<auto*>– tkausl
Nov 19 '18 at 16:11
2
2
You should list the problems that polymorphism (built-in runtime polymorphism in case of
virtual functions being involved) was invented to solve and explain for each problem how it could be solved with auto. Your current "just say that the function func is receiving auto param" makes no sense.– VTT
Nov 19 '18 at 16:17
You should list the problems that polymorphism (built-in runtime polymorphism in case of
virtual functions being involved) was invented to solve and explain for each problem how it could be solved with auto. Your current "just say that the function func is receiving auto param" makes no sense.– VTT
Nov 19 '18 at 16:17
add a comment |
1 Answer
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No, auto cannot solve any of those problems.
auto is a compile-time utility to deduce the type of a thing from the code that's around it. It is more closely related to templates (indeed, the auto in the parameter list of a lambda is implemented by a template!).
It has no knowledge of runtime states and cannot be used to perform virtual dispatch.
These are completely different concepts and your best bet would be to re-study what each one means.
answered Nov 19 '18 at 16:11
Lightness Races in Orbit
284k51460781
Thank you. I was told that auto has runtime knowledge.
– Or251
Nov 19 '18 at 16:19
Andautovariables use (slightly addended) template type deduction to tun into a concrete type.
– Quentin
Nov 19 '18 at 16:19
2
@Or251 Tell whoever told you that to come here for a lesson ;)
– Lightness Races in Orbit
Nov 19 '18 at 16:22
1
@Or251 ... or, print the current standard draft and hit said person hard with it. (For best effect not only print the relevant section but the whole draft ;)
– Swordfish
Nov 19 '18 at 16:27
add a comment |
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1 Answer
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votes
No, auto cannot solve any of those problems.
auto is a compile-time utility to deduce the type of a thing from the code that's around it. It is more closely related to templates (indeed, the auto in the parameter list of a lambda is implemented by a template!).
It has no knowledge of runtime states and cannot be used to perform virtual dispatch.
These are completely different concepts and your best bet would be to re-study what each one means.
answered Nov 19 '18 at 16:11
Lightness Races in Orbit
284k51460781
Thank you. I was told that auto has runtime knowledge.
– Or251
Nov 19 '18 at 16:19
Andautovariables use (slightly addended) template type deduction to tun into a concrete type.
– Quentin
Nov 19 '18 at 16:19
2
@Or251 Tell whoever told you that to come here for a lesson ;)
– Lightness Races in Orbit
Nov 19 '18 at 16:22
1
@Or251 ... or, print the current standard draft and hit said person hard with it. (For best effect not only print the relevant section but the whole draft ;)
– Swordfish
Nov 19 '18 at 16:27
add a comment |
No, auto cannot solve any of those problems.
auto is a compile-time utility to deduce the type of a thing from the code that's around it. It is more closely related to templates (indeed, the auto in the parameter list of a lambda is implemented by a template!).
It has no knowledge of runtime states and cannot be used to perform virtual dispatch.
These are completely different concepts and your best bet would be to re-study what each one means.
answered Nov 19 '18 at 16:11
Lightness Races in Orbit
284k51460781
Thank you. I was told that auto has runtime knowledge.
– Or251
Nov 19 '18 at 16:19
Andautovariables use (slightly addended) template type deduction to tun into a concrete type.
– Quentin
Nov 19 '18 at 16:19
2
@Or251 Tell whoever told you that to come here for a lesson ;)
– Lightness Races in Orbit
Nov 19 '18 at 16:22
1
@Or251 ... or, print the current standard draft and hit said person hard with it. (For best effect not only print the relevant section but the whole draft ;)
– Swordfish
Nov 19 '18 at 16:27
add a comment |
No, auto cannot solve any of those problems.
auto is a compile-time utility to deduce the type of a thing from the code that's around it. It is more closely related to templates (indeed, the auto in the parameter list of a lambda is implemented by a template!).
It has no knowledge of runtime states and cannot be used to perform virtual dispatch.
These are completely different concepts and your best bet would be to re-study what each one means.
answered Nov 19 '18 at 16:11
Lightness Races in Orbit
284k51460781
No, auto cannot solve any of those problems.
auto is a compile-time utility to deduce the type of a thing from the code that's around it. It is more closely related to templates (indeed, the auto in the parameter list of a lambda is implemented by a template!).
It has no knowledge of runtime states and cannot be used to perform virtual dispatch.
These are completely different concepts and your best bet would be to re-study what each one means.
answered Nov 19 '18 at 16:11
Lightness Races in Orbit
284k51460781
answered Nov 19 '18 at 16:11
Lightness Races in Orbit
284k51460781
answered Nov 19 '18 at 16:11
Lightness Races in Orbit
284k51460781
answered Nov 19 '18 at 16:11
Lightness Races in Orbit
284k51460781
284k51460781
Thank you. I was told that auto has runtime knowledge.
– Or251
Nov 19 '18 at 16:19
Andautovariables use (slightly addended) template type deduction to tun into a concrete type.
– Quentin
Nov 19 '18 at 16:19
2
@Or251 Tell whoever told you that to come here for a lesson ;)
– Lightness Races in Orbit
Nov 19 '18 at 16:22
1
@Or251 ... or, print the current standard draft and hit said person hard with it. (For best effect not only print the relevant section but the whole draft ;)
– Swordfish
Nov 19 '18 at 16:27
add a comment |
Thank you. I was told that auto has runtime knowledge.
– Or251
Nov 19 '18 at 16:19
Andautovariables use (slightly addended) template type deduction to tun into a concrete type.
– Quentin
Nov 19 '18 at 16:19
2
@Or251 Tell whoever told you that to come here for a lesson ;)
– Lightness Races in Orbit
Nov 19 '18 at 16:22
1
@Or251 ... or, print the current standard draft and hit said person hard with it. (For best effect not only print the relevant section but the whole draft ;)
– Swordfish
Nov 19 '18 at 16:27
Thank you. I was told that auto has runtime knowledge.
– Or251
Nov 19 '18 at 16:19
Thank you. I was told that auto has runtime knowledge.
– Or251
Nov 19 '18 at 16:19
And
auto variables use (slightly addended) template type deduction to tun into a concrete type.– Quentin
Nov 19 '18 at 16:19
And
auto variables use (slightly addended) template type deduction to tun into a concrete type.– Quentin
Nov 19 '18 at 16:19
2
2
@Or251 Tell whoever told you that to come here for a lesson ;)
– Lightness Races in Orbit
Nov 19 '18 at 16:22
@Or251 Tell whoever told you that to come here for a lesson ;)
– Lightness Races in Orbit
Nov 19 '18 at 16:22
1
1
@Or251 ... or, print the current standard draft and hit said person hard with it. (For best effect not only print the relevant section but the whole draft ;)
– Swordfish
Nov 19 '18 at 16:27
@Or251 ... or, print the current standard draft and hit said person hard with it. (For best effect not only print the relevant section but the whole draft ;)
– Swordfish
Nov 19 '18 at 16:27
add a comment |
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1
Correct me if i'm wrong, but the keyword "auto" can solve all the problems that polymorphism was invented to solve.You're wrong. Try for examplestd::vector<auto*>– tkausl
Nov 19 '18 at 16:11
2
You should list the problems that polymorphism (built-in runtime polymorphism in case of
virtualfunctions being involved) was invented to solve and explain for each problem how it could be solved withauto. Your current "just say that the function func is receiving auto param" makes no sense.– VTT
Nov 19 '18 at 16:17