int incr2(int& value) { value = value + 1; return value; }

is the same as

int incr3(int* value) { (*value) = (*value) + 1; return *value; }

and they will be used diferently for the same result :

void main() {

  int a_value = 5;

  int result2 = incr2(a_value); // result2 = a_value = 6;
  int result3 = incr3(&a_value); // resulst3 = a_value = 7;

in the call to incr3 "&a_value" can be read : address_of "a_value".

and in the body of incr3 "*value" can be read : content of address "value".

and finnaly in the prototype "int incr3(int* value)", "int*" can be read : pointer to an int, or address of an int.

pointer/address are a fundamental concept for programming at large, the concept of "indirection".

all this may seem unrelated at first, but in your Complex problem, you can try something like :

#include

...

Complex c2;

std::cout << &c2 /* address of c2 */ << std::endl;

and in your copy constructor :

Complex(Complex& c) {

  std::cout << &c /\* address of c \*/ << std::endl;

  ...

you will see that, with a reference, the addresses are the sames, but without references you will get different addresses meaning that your variables are'nt the same (in the case of function parameters/arguments they are copies of the parameters values, that's why we call this "pass by value" semantic, rather than "pass by reference" or "pass by address" or box, or indirection, or whatever having the same meaning).

hope this help.

it never pass c2 to the copy constructor.

a) it pass a reference to it, if the copy constructor is defined as "Complex(Complex& refr)"

b) it pass a copy of it, if the copy constructor is defined as "Complex(Complex copy).

just dont consider references in the context of objects or copy constructors, but in the context of a simple function :

int incr1(int value) { value = value + 1; return value; }

vs

int incr2(int& value) { value = value + 1; return value; }

in incr1 value is local to the function, it is a copy of the value you pass as parameter

in incr2 it is'nt local to the function, there is no copy done.

// not tested sample :

#include

void main() {

  int a_value = 2;

  int result1 = incr1(a_value); // no reference, a copy, local to the function, is made.
  assert(a_value == 2);         // ok
  assert(result1 == 3);         // ok

  int result2 = incr2(a_value); // with reference, there is no copy made.
  assert(a_value == 2);         // error, the original a_value parameter as been incremented.
  assert(a_value == 3);         // ok
  assert(result2 == 3);         // ok

the incr1 is more "secure" (it is said "pure", for this and others reasons), but it always make a temporary int that is a copy of the parameter you give to it.

the incr2 is less "secure", but there is no temporary int created.

that's exactly to prevent the temporary int/Complex that copy constructors always require a reference, because when you call the copy constructor explicitly (in : Complex c3(c2); ), the copy constructor for the temporary will be called implicitly too, and the copy constructor for the temporary of the temporary called implicitly will be called implicitly too, etc.

hope this help.

without defining a copy constructor, the compiler will do the copy himself, the point is : there is no copy constructor to call, so you have :

1) first the new Complex c3 is allocated,

2) there is no copy constructor to call

3) the compiler do the job, the memory used by c2 is copied on c3.

end of the story, no parameter value.

when adding a legal copy constructor (pass by reference), you may consider the reference like some sort of pointer. this is false, but help to understand the memory behavior of a copy constructor. then you have something like :

1) first the new Complex c3 is allocated

2) the "memory" for c, the reference/pointer to c2, is allocated.

3) the _address_ of c2 is copied in c.

4) the c3 constructor start with the reference/pointer/address of c2 as parameter.

end of the story, normal "pass by value" of an address.

finaly, if a copy constructor _without_ reference/pointer was legal, you will have:

1) first the new Complex c3 is allocated,

2) another new Complex, the c3 copy constructor parameter value c, is allocated.

3) instead of directly copying c2 memory to c, there is the c copy constructor to call (with a copy of c2 as parameter value)

4) another new Complex c_bis, the c copy constructor parameter value (c), is allocated.

5) instead of directly copying c2 memory to c_bis there is the c_bis copy constructor to call (with a copy of c2 as parameter value)

6) another new Complex c_bis_bis is allocated ... etc.

the problem is that a copy constructor is _implicitly_ called to create a copy, which transform a pass by value semantic in an infinite loop of allocations on the stack.

hope this help.

none of thoses sources is contradictory of what i explained on the history of our shortages.

> Why did you chose hydro?

because you talk about mix, today its fr secondary electricity production, and hydro plants are older than fr nuclear plants/projects.

>That is half of what EPR needs to invest to keep your ageing fleet from falling apart...

i'm not sure of what your talking about again, that's probably half or even less of what we must invest to keep our ageing (not EPR) nuclear fleet yes, which provide 75% of our production, in other words: 8% production for 50billions imported external products + exploitation cost on 20years vs 75% for 50billions local supply one shot to add 20 years to the current fleet, the choice is easy technicaly speaking (not politicaly). our ageing fleet is not linked to EPR at all which may be considered as a prototype for an eventual next fleet, we will see, and as already explained, the cost of our first EPR is not the cost of an EPR in a future fleet. side note: most of our ageing fleet have been build in only 10 years after 20 years of research and "prototypes".

> you just accepted to ignore all the costs generations will have to come up with just to cover nuclear waste

we started a project in 2000 for longterm deep storage which will provide waste stockage for more than 100years of our current dangerous waste production ( https://fr.wikipedia.org/wiki/Laboratoire_de_Bure ), for less dangerous product we are already treating not only our waste but most of the EU nuclear waste.

> You said that safety costs too much and we should look to China...

no i said our safety changes extended cost and delay, while china without changes respected cost and delay. which imply that our acquired expertise _with_ safety changes will probably respect and reduce cost like delay if we produce more EPR. this does'nt mean and i never said that we must do like china, that's your straw man.

> The fact that while nuclear only gets more expensive

source ? for the same type of product nuclear does'nt get more expensive, what get more expensive is more efficient, more secured, better and new/first try nuclear plants

> renewables not only got cheaper

renewable cost is a market cost not a local/production cost, like lithium for batteries, china got a mostly exclusive (quantitavely speaking) market on solar and parts of wind turbines (and for a time lithium) not by lowering cost but to acquire the market. we will talk about renewables production cost when they will be produced with renewables energy sources and not charcoal, gaz, gas and nuclear sources. yes nuclear actually rely on the same energy sources with one big diffence: it does'nt rely on it all it's lifetime.

> Why don't you link your study

because you have'nt link your "contradictory old study" and like i already said, to compare them they must apply to the same subject. but if you really want sources on this topic and a lot more about the same subject, there is the 20 hours videos of courses of the "ecole des mines", one of the two or three most recognized schools in fr (largely better than any master or ph.d) :

https://www.youtube.com/watch?v=xgy0rW0oaFI&list=PLMDQXkItOZ...

you may find the site of the professor in the link which will provide a lot more ressources on nuclear and climate data and expertise, and probably some sources in english.

> You must know about the energy shortages

yes and you seem to not realize that those energy shortages are only on our own production, most of them where usually compensated by introducing/buying energy from others EU country with some minor exceptions like lowering the max available power on smalls customer populations and in rare case short cuts; no critical supply was ever stoped, no home get total shot down for more than a few hours, if those happens that was for small sets, nothing comparable to (for example, even if not linked to production i think) what happened in texas last winter, even occasional energy cut for technical problems which happen to all electry energy supply in all countries are worse than those "production shortages".

> you still chose to lie about it ? why ?

i'm not lying, you just seem to simply not knowing what you'r talking about, building some sort of fantasy disaster looking everywhere on google to confirm your bias (which will always be a success whatever may be the topic of your fantasy).

yes and all your sources are post 2019 (the fessenheim reactor has been slowed since 2017, the project/idea to close it started in 2012, and the effective (not reversible) closing has happened on feb 2020 while it was stopped since more than 2 years) dont really see what's your point here...

> This is why you diversify your energy.

no, our electric mix was simply not build on nuclear, hydroelectric and charcoal was our first power source, nuclear allowed us to close charcoal mines and plants while fullfilling the growing electric needs. nuclear is'nt without constrains that hydroelectric dont have, however there is not much more places to have new hydros. "renewables" will maybe goes up to 8% in the coming years and has already cost us more than 50billions€ (governement subvention) which is nearly two time our current non running EPR cost :) note that those 50billions was only for deployment they does'nt include exploitation cost, that's a big difference between wind turbines and nuclear, nuclear cost is mostly capitalistic (start investment for 60years in the case of an EPR) while wind turbine cost must be evaluated over their full lifetime including market fluctuations, try to evaluate that for the 60 years comming, good luck!

> Yeah they should just look away more like in China...

what's your point here again ? changing a project constrain while it is already started add cost and delay, however once done, acquired expertise usually reduce cost and delay. we have choosen our way to do it, probably for good reasons.

> but I can't take such statements seriously. It's madness.

actually this is your statement, your making a straw man here.

> there was a study years ago

what let you think that an old study with probably outdated constrains and knowledges would be more serious than actual studies from recognized sources (ecole polytechnique, les mines) ? and more important, those studies to be comparable must have the same subject, replacing nuclear with wind turbines is not the same as replacing nuclear + transportation(gas) for example. with the current urge (climatical and political) to reduce gas based transportations, there is also an urge/need to grow electric supply up to two time the actual production (unless your looking for economical collapse by replacing gas with nothing). from this point of view, current renewable are just a joke in france since we have no industries on renewables (they poorly failed/died) which means we will be fully dependent on external supply, and yes that's madness.

ho one last point, those studies are usually done with wind turbine because solar panels end up using a lot more surface than wind turbines, that let you think of the surface needs with a mix of the two...

> this is France we're talking about. Those informations are easy to google.

actually i'm french and in france (in case my poor english was'nt a sufficient hint), those subjects are a perpetual technical and political debate here, i dont really need google press report to explain me what i'm living (actually its a known fact that press is'nt an opposable source in techical subjects, try google schoolar maybe...) :)

this missing capacity is less the usual slowdown of reactors because of the hot rivers (which by the way is done for environmental and not technical concern) and maintenances process, than a consequence of a previous nuclear plant closing (for political/electoral reasons). another consequence of this missing plant was to reopen two charcoal power plant _this_winter_.

a large part of the EPR slowdown in fr is due to security concern that changed while the project was already started, china EPRs which was similar but a lot less constrained was done in time.

on the price: 25% of the energy produced by nuclear in fr is sold under the market price to private retailers because of anti-monopolistic EU laws and stupidity of our governement. the electricity price in EU is usualy indexed on the worst gaz plant available, with the actual price of gaz raising and all of the 25% already acquired, a lot of them are just closing.

given those constrains, yes this model works more than well...

the project to close "50%" (in fact 15 reactors) until 2030 is another political subject which will probably never become a reality given that most renewable alternatives projects end up being blocked/hated everywhere.

funny fact: replacing ALL the current transport and electric energy supply in fr by wind turbines has been evaluated to require one of the most efficient available turbine for each km² on ALL the french territory...

there is no doubt on that, we're evolving, we're even able to trace some minor genetic evolutions over the 7k last years. but the cultural myth of "natural selection" or "naturally" evolving is in the question : what is "natural" and by extension, what is'nt ? kin evolution or social behaviors always end up as reproduction success, and the failure to do so, "naturally" or "artificially" end up in extinction, that's all. there is nothing specifically "natural" or "artificial" here. when talking about genetics the involved time scales badly fit cultural consideration like thoses. it is not less "natural" to gain reproductive success by genetic intervention than without, unless you are able to explain what is this "nature". or in other words : there is nothing to bypass unless you'r able to say/describe/explain what :)