a BOOL veriable

Yochanan Gerbi 2012.11.27 21:23

Hello freinds,

We say that:

Boolean constants may have the value of true or false, numeric representation of them is 1 or 0, respectively. True or TRUE, False or FALSE can be used, as well.

Examples:

bool a = true;
bool b = false;
bool c = 1;

Its internal representation is a long 4-byte integer number. Boolean constants can assume the values of 0 or 1.

I have a problem, and I nnd your help:

The code lines are:

...

bool alfa[19];

int beta[50][300];

int gamma[50];

...

alfa[1] = 1;

...

beta[0][11] = alfa[9] * gamma[9] + !alfa[9] * StrToTime("00:00");

My quations are:

Do I right if I say: a bool variable is 0 if it is FALSE, and a bool variable is 1 if it is TRUE?

and:

Why do I get an error massage on the last code line - "=" - assignment expected ?

Please help.

Thanks,

kronin 2012.11.27 22:34 #1

crossy:

Hello freinds,

We say that:

Boolean constants may have the value of true or false, numeric representation of them is 1 or 0, respectively. True or TRUE, False or FALSE can be used, as well.

Examples:

Its internal representation is a long 4-byte integer number. Boolean constants can assume the values of 0 or 1.

I have a problem, and I nnd your help:

The code lines are:

...

bool alfa[19];

int beta[50][300];

int gamma[50];

...

alfa[1] = 1;

...

beta[0][11] = alfa[9] * gamma[9] + !alfa[9] * StrToTime("00:00");

My quations are:

Do I right if I say: a bool variable is 0 if it is FALSE, and a bool variable is 1 if it is TRUE?

and:

Why do I get an error massage on the last code line - "=" - assignment expected ?

Please help.

Thanks,

Question 1: right.

What exactly do you try to achieve with that line of code? You mix up different data types.

Simon Gniadkowski 2012.11.27 22:39 #2

crossy:

Hello freinds,

We say that:

Boolean constants may have the value of true or false, numeric representation of them is 1 or 0, respectively. True or TRUE, False or FALSE can be used, as well.

I don't say that . . .

Think of a bool as True or False . . . forget 0 and 1 . . . where is the logic of trying to do bool * int ? what goes true * 5 mean ? very true ?

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Yochanan Gerbi 2012.11.27 23:50 #3

RaptorUK:

I don't say that . . .

Think of a bool as True or False . . . forget 0 and 1 . . . where is the logic of trying to do bool * int ? what goes true * 5 mean ? very true ?

Thanks Raptor,

Exactly. I agree with you.

My decompiler returned it so. Is there any possibilty to understand it....? I need your help!!

Yochanan Gerbi 2012.11.28 05:26 #4

crossy:

Thanks Raptor,

Exactly. I agree with you.

My decompiler returned it so. Is there any possibilty to understand it....? I need your help!!

Any one can help?

kronin 2012.11.28 06:10 #5

crossy:

Any one can help?

I don't think there is a possibility to understand why different datatypes should be added/multiplicated together. And I am not sure about you should ask questions for decompiled code. However, put !alfa[9] in brackets - (!alfa[9]) - and you have a chance it does compile.
edit: Of course you can e.g. multiplicate a double with an integer and assign it to a double.

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Simon Gniadkowski 2012.11.28 07:23 #6

crossy:

Thanks Raptor,

Exactly. I agree with you.

My decompiler returned it so. Is there any possibilty to understand it....? I need your help!!

Decompiler ? please explain . . .

William Roeder 2012.11.28 12:10 #7

IMO, there is only one reason to use bool * x and only if you think it simplifies the reading of the code. Variations like:

Explicit	Compact
if (isSomething) double x = A; else x = B;	double x = isSomething * A + !isSomething * B;
double x = A; if (isSomething) x += B;	double x = A + isSomething * B;

Yochanan Gerbi 2012.11.28 12:54 #8

kronin:

I don't think there is a possibility to understand why different datatypes should be added/multiplicated together. And I am not sure about you should ask questions for decompiled code. However, put !alfa[9] in brackets - (!alfa[9]) - and you have a chance it does compile.
edit: Of course you can e.g. multiplicate a double with an integer and assign it to a double.

Thanks kronin, It works!!.

Yochanan Gerbi 2012.11.28 12:55 #9

WHRoeder:
IMO, there is only one reason to use bool * x and only if you think it simplifies the reading of the code. Variations like:

Explicit	Compact

Very intelegent way to solve it.

Thanks WMR

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