variables and values

[none]

hi all, i'm very new to php and i'm a little confused about something.
this will be dead simple to the rest of you but it doesn't work for
me.

i have a variable called "$a" which has a value of 10.

i want to pass this value to a new variable and increase it by 10, is
this the right way?

$a=$b;
$b + 10;

thanks for not laughing :o)

[Ian.H]

Re: variables and values

On Fri, 02 Apr 2004 10:31:47 -0800, none wrote:
[color=blue]
> hi all, i'm very new to php and i'm a little confused about something.
> this will be dead simple to the rest of you but it doesn't work for
> me.
>
> i have a variable called "$a" which has a value of 10.
>
> i want to pass this value to a new variable and increase it by 10, is
> this the right way?
>
> $a=$b;
> $b + 10;
>
> thanks for not laughing :o)[/color]


What you have is perfectly "legal" and will work.. however, if you want to
tidy it up:


$b = $a + 10;


If you don't _really_ need to pass it to another value and just +10 to it,
you can use:


$a +=10;


This is the same as:


$a = $a + 10;


I realise this might not be what you're after (second example) but may be
of use for the future if you were unaware =)


HTH.



Regards,

Ian

--
Ian.H
digiServ Network
London, UK

http://digiserv.net/

[Pedro Graca]

Re: variables and values


Hi none! Welcome to PHP.

none wrote:[color=blue]
> i have a variable called "$a" which has a value of 10.
>
> i want to pass this value to a new variable and increase it by 10, is
> this the right way?
>
> $a=$b;[/color]

This puts into $a the contents of $b;

How did $a get to have the value of 10?
You didn't do "10=$a;" (parse error) -- this doesn't work because you
can't change the value 10. The 'thing' being changed _always_ (*) goes
on the left side of the equals sign.

To make $b have the same thing $a has do

$b = $a;

[color=blue]
> $b + 10;[/color]

This one is not changing any variable -- it just calculates the value
and then ignores it because there is no instruction to do something with
that value; you want to put that value into a variable, so you have to
say that to PHP:

$b = $b + 10;

Which means "add the contents of $b to 10 and save the resulting value
in $b".


(*) but some things can be changed on the right side too, or even
without an equals sign :)

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[Ian.H]

Re: variables and values

On Fri, 02 Apr 2004 18:42:55 +0000, Ian.H wrote:
[color=blue]
> On Fri, 02 Apr 2004 10:31:47 -0800, none wrote:
>[color=green]
>> hi all, i'm very new to php and i'm a little confused about something.
>> this will be dead simple to the rest of you but it doesn't work for
>> me.
>>
>> i have a variable called "$a" which has a value of 10.
>>
>> i want to pass this value to a new variable and increase it by 10, is
>> this the right way?
>>
>> $a=$b;
>> $b + 10;
>>
>> thanks for not laughing :o)[/color]
>
>
> What you have is perfectly "legal" and will work.. however, if you want to
> tidy it up:
>
>
> $b = $a + 10;[/color]


Oops!

After reading Pedro's post below.. I realised I made a massive error here =[

Pedro is correct.. please excuse and ignore my reply about the above being
correct.

The following _is_ correct (just for my own FWIW =) ):


$b = $a;
$b =+ 10;

$b = $a + 10;

$b = $a;
$b = $b + 10;


All of these will work.. but your choice which is preferable (#2) =)



Regards,

Ian

--
Ian.H
digiServ Network
London, UK

http://digiserv.net/

[Andy Hassall]

Re: variables and values

On Fri, 02 Apr 2004 19:30:39 GMT, "Ian.H" <ian@WINDOZEdig iserv.net> wrote:
[color=blue]
>The following _is_ correct (just for my own FWIW =) ):
>
> $b =+ 10;[/color]

*polite cough* ;-) Isn't that:

'$b' 'assignment' 'unary positive' 'constant integer 10' ?

You mean $b += 10...

--
Andy Hassall <andy@andyh.co. uk> / Space: disk usage analysis tool
http://www.andyh.co.uk / http://www.andyhsoftware.co.uk/space

[Chung Leong]

}Re: variables and values


"none" <kinskai@aol.co m> wrote in message
news:863d38a1.0 404021031.59d29 d33@posting.goo gle.com...[color=blue]
> hi all, i'm very new to php and i'm a little confused about something.
> this will be dead simple to the rest of you but it doesn't work for
> me.
>
> i have a variable called "$a" which has a value of 10.
>
> i want to pass this value to a new variable and increase it by 10, is
> this the right way?
>
> $a=$b;
> $b + 10;
>
> thanks for not laughing :o)[/color]

This is the right way to do it, I think:

class Number {
$value;

function Number($value) {
$this->value = $value;
}

function ToString() {
return $this->value;
}

function GetValue() {
return $this->value;
}

function Clone() {
return $this;
}
}

class RealInteger extends Number {
function RealInteger($va lue) {
$this->Number($value) ;
}

function IsPositive() {
return ($this->value >= 0);
}

function Add($increment) {
$this->value += $increment;
return $this->value;
}

function Minus($incremen t) {
$this->value -= $increment;
return $this->value;
}
}

class CustomRealInteg er extends RealInteger {
function CustomRealInteg er($value = 0) {
$this->RealInteger($v alue);
}

function IncreaseByTen() {
return $this->Add(10);
}
}

$a = new CustomRealInteg er(5);
$b = $a->Clone();
$b->IncreaseByTen( );

[none]

Re: variables and values

Pedro Graca <hexkid@hotpop. com> wrote in message news:<c4kcee$2j 162r$1@ID-203069.news.uni-berlin.de>...[color=blue]
> Hi none! Welcome to PHP.
>
> none wrote:[color=green]
> > i have a variable called "$a" which has a value of 10.
> >
> > i want to pass this value to a new variable and increase it by 10, is
> > this the right way?
> >
> > $a=$b;[/color]
>
> This puts into $a the contents of $b;
>
> How did $a get to have the value of 10?
> You didn't do "10=$a;" (parse error) -- this doesn't work because you
> can't change the value 10. The 'thing' being changed _always_ (*) goes
> on the left side of the equals sign.
>
> To make $b have the same thing $a has do
>
> $b = $a;
>
>[color=green]
> > $b + 10;[/color]
>
> This one is not changing any variable -- it just calculates the value
> and then ignores it because there is no instruction to do something with
> that value; you want to put that value into a variable, so you have to
> say that to PHP:
>
> $b = $b + 10;
>
> Which means "add the contents of $b to 10 and save the resulting value
> in $b".
>
>
> (*) but some things can be changed on the right side too, or even
> without an equals sign :)[/color]


Beuty, all working!!!

[Filth]

Re: variables and values

[color=blue]
> This is the right way to do it, I think:
>
> class Number {
> $value;
>
> function Number($value) {
> $this->value = $value;
> }
>
> function ToString() {
> return $this->value;
> }
>
> function GetValue() {
> return $this->value;
> }
>
> function Clone() {
> return $this;
> }
> }
>
> class RealInteger extends Number {
> function RealInteger($va lue) {
> $this->Number($value) ;
> }
>
> function IsPositive() {
> return ($this->value >= 0);
> }
>
> function Add($increment) {
> $this->value += $increment;
> return $this->value;
> }
>
> function Minus($incremen t) {
> $this->value -= $increment;
> return $this->value;
> }
> }
>
> class CustomRealInteg er extends RealInteger {
> function CustomRealInteg er($value = 0) {
> $this->RealInteger($v alue);
> }
>
> function IncreaseByTen() {
> return $this->Add(10);
> }
> }
>
> $a = new CustomRealInteg er(5);
> $b = $a->Clone();
> $b->IncreaseByTen( );[/color]

dont you think that is a bit overkill for someone who just wants to know how
to add 10 to a variable

[Agelmar]

Re: variables and values

Chung Leong wrote:[color=blue]
> "none" <kinskai@aol.co m> wrote in message
> news:863d38a1.0 404021031.59d29 d33@posting.goo gle.com...[color=green]
>> hi all, i'm very new to php and i'm a little confused about
>> something. this will be dead simple to the rest of you but it
>> doesn't work for me.
>>
>> i have a variable called "$a" which has a value of 10.
>>
>> i want to pass this value to a new variable and increase it by 10, is
>> this the right way?
>>
>> $a=$b;
>> $b + 10;
>>
>> thanks for not laughing :o)[/color]
>
> This is the right way to do it, I think:
>
> class Number {[/color]
<snip>

LMFAO, I can't stop laughing...

[Ian.H]

Re: variables and values

On Fri, 02 Apr 2004 21:08:24 +0100, Andy Hassall wrote:
[color=blue]
> On Fri, 02 Apr 2004 19:30:39 GMT, "Ian.H" <ian@WINDOZEdig iserv.net> wrote:
>[color=green]
>>The following _is_ correct (just for my own FWIW =) ):
>>
>> $b =+ 10;[/color]
>
> *polite cough* ;-) Isn't that:
>
> '$b' 'assignment' 'unary positive' 'constant integer 10' ?
>
> You mean $b += 10...[/color]


Wow! today _really_ wasn't my day lol.

Thanks for pointing out this (additional) error. I'm just glad I post here
fairly frequently with some working answers.. I'd look a right prick
otherwise.. or a m$ employee (don't they fix bugs with more bugs? =) ).

Thanks Andy for pointing this out.. and you're correct, I did mean '+='
rather than '=+'.

Can I just pretent that $a was defined as 0? =D



Regards,

Ian

--
Ian.H
digiServ Network
London, UK

http://digiserv.net/

[Jeffrey Silverman]

Re: variables and values

On Sat, 03 Apr 2004 12:49:23 +0100, Filth wrote:
[color=blue]
> dont you think that is a bit overkill for someone who just wants to know how
> to add 10 to a variable[/color]

For the humor impaired, Chung's post was pretty likely a joke.

--
Jeffrey D. Silverman | jeffrey AT jhu DOT edu
Website | http://www.wse.jhu.edu/newtnotes/