problems on using the if and else statement and updating the data.

Mr.Nobody645

im appreciate for both of you on helping me in the if and else part. However, when i try to checked AddOn1 and AddOn2, i got my price 2.50 instead of 3.70.

J.Hilk

@Mr-Nobody645 said in problems on using the if and else statement and updating the data.:

im appreciate for both of you on helping me in the if and else part. However, when i try to checked AddOn1 and AddOn2, i got my price 2.50 instead of 3.70.

obviously, as

if (ui-> AddOn1 -> isChecked()){
price = 2.50;
}

comes before everything else and its true so the rest of the checks is not executed

JonB

@Mr-Nobody645 said in problems on using the if and else statement and updating the data.:

However, when i try to checked AddOn1 and AddOn2, i got my price 2.50 instead of 3.70.

That's why I wrote earlier:

In which case you'll need to test that [if (ui-> AddOn1-> isChecked() && ui-> AddOn2-> isChecked())] before testing ui-> AddOn1-> isChecked() or ui-> AddOn2-> isChecked() individually.

JonB

@sierdzio said in problems on using the if and else statement and updating the data.:

All modernt compilers also understand and as a synonym to && so you can do:

I am speechless! Apart from the fact that I have never heard of this (old time C/C++ programmer, now returned to new C++). And apart from the fact that introducing and as a language keyword would potentially break one million old C/C++ programs which could have used and as a variable?

You are obviously more expert than I, but do you want to recommend this to a newbie? I have never noticed and used in a C++ program, if OP is to produce standard code, and recognize others' code, would you not recommend sticking with &&?

J.Hilk

@JonB apparently part of the standard since c++98
https://en.cppreference.com/w/cpp/keyword/and

JonB

@J-Hilk , @sierdzio
Absolutely shocking! I see from https://en.cppreference.com/w/cpp/language/operator_alternative that there are actually 11 new reserved words for operators. Including not, and even the string compl, which I might have used as variables and would break upgrading to C++ '98.

Thinking aloud, I believe all C operators were symbols and not words, part of the charm (for right or for wrong) of the language.

With all due respect to @sierdzio's comment, which I accept & respect, I have still never seen a piece of C++ code using any of these.... [And hence would caution a beginner against adopting these.]

[C++ looks like it's trying to be a Python-wannabe ;-) ]

jsulm

@JonB said in problems on using the if and else statement and updating the data.:

I have still never seen a piece of C++ code using any of these

Me neither :-)

sierdzio

I have seen it but very, very rarely.

And hence would caution a beginner against adopting these

I'm split on this :D One one hand, && is clearly, vastly, totally the established and well-known convention practically everywhere. So using it is definitely a good idea.

But on the other hand, and is more readable and convenient. So it is also a good idea.

JonB

@sierdzio said in problems on using the if and else statement and updating the data.:

But on the other hand, and is more readable and convenient.

In Pascal or Python, yes. When scanning C/C++ I expect to see all operators as symbols (and not some but not others) Next C++ will be offering begin/end for {/}! [Some people used to do all this words-for-symbols via C #defines.] I give up on the modern world, it's all going to pot... ;-)

J.Hilk

@JonB said in problems on using the if and else statement and updating the data.:

Next C++ will be offering begin/end for {/}!

you can use

{	??<
}	??>
[	??(
]	??)
#	??=
\	??/
^	??'
|	??!
~	??-

but that was removed in c++17, :)

JonB

@J-Hilk

but that was removed in c++17, :)

Even better --- you start using new language constructs and then they remove them so that your code gets broken!

FWIW, I note from https://en.cppreference.com/w/cpp/language/operator_alternative

There are alternative spellings for several operators and other tokens that use non-ISO646 characters.

So the motivation never was "clarity", it's to do with people having funny keyboards....

SGaist

@JonB said in problems on using the if and else statement and updating the data.:

funny keyboards

The hardware is innocent ;-P

Kent-Dorfman

whats next, espousing the virtues of trigraphs?

1Manui1

How did you do it now?