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digitalmars.D.learn - is there "this"?

reply Konstantin Kutsevalov <adamasantares gmail.com> writes:
The question is simple.

Is there something like "this" word for classes?

For example:

```
class CLS {

     int numberValue;

     public this(numberValue)
     {
         // how can I put the local numberValue to class property?
         // in some prog language I can do like:
         // this.numberValue = numberValue;
     }

}
```
Nov 01 2016
parent reply rikki cattermole <rikki cattermole.co.nz> writes:
On 02/11/2016 3:17 PM, Konstantin Kutsevalov wrote:

 The question is simple.

 Is there something like "this" word for classes?

 For example:

 ```
 class CLS {

     int numberValue;

     public this(numberValue)
     {
         // how can I put the local numberValue to class property?
         // in some prog language I can do like:
         // this.numberValue = numberValue;
     }

 }
 ```


You forgot an int in the arguments but otherwise that would work fine 
with your line uncommented.
Nov 01 2016
parent reply Konstantin Kutsevalov <adamasantares gmail.com> writes:
On Wednesday, 2 November 2016 at 02:20:43 UTC, rikki cattermole 
wrote:

 On 02/11/2016 3:17 PM, Konstantin Kutsevalov wrote:

 The question is simple.

 Is there something like "this" word for classes?

 For example:

 ```
 class CLS {

     int numberValue;

     public this(numberValue)
     {
         // how can I put the local numberValue to class 
 property?
         // in some prog language I can do like:
         // this.numberValue = numberValue;
     }

 }
 ```


 You forgot an int in the arguments but otherwise that would 
 work fine with your line uncommented.


yes I missed "int", but it's just an example.
so if I'll write "this.property = value" it will work?
Nov 01 2016
parent reply Konstantin Kutsevalov <adamasantares gmail.com> writes:
On Wednesday, 2 November 2016 at 02:33:10 UTC, Konstantin 
Kutsevalov wrote:

 On Wednesday, 2 November 2016 at 02:20:43 UTC, rikki cattermole 
 wrote:

 On 02/11/2016 3:17 PM, Konstantin Kutsevalov wrote:

 The question is simple.

 Is there something like "this" word for classes?

 For example:

 ```
 class CLS {

     int numberValue;

     public this(numberValue)
     {
         // how can I put the local numberValue to class 
 property?
         // in some prog language I can do like:
         // this.numberValue = numberValue;
     }

 }
 ```


 You forgot an int in the arguments but otherwise that would 
 work fine with your line uncommented.


 yes I missed "int", but it's just an example.
 so if I'll write "this.property = value" it will work?


I tested already and it really works, thank you.
I asked that because I tried once to use "this" in past but I got 
error. So I asked on some forum "how to get property of class?" 
and peoples said that I may use just a name of property. So I 
thought that there isn't "this" word.
Nov 01 2016
next sibling parent reply Bauss <jj_1337 live.dk> writes:
On Wednesday, 2 November 2016 at 02:42:01 UTC, Konstantin 
Kutsevalov wrote:

 On Wednesday, 2 November 2016 at 02:33:10 UTC, Konstantin 
 Kutsevalov wrote:

 On Wednesday, 2 November 2016 at 02:20:43 UTC, rikki 
 cattermole wrote:

 On 02/11/2016 3:17 PM, Konstantin Kutsevalov wrote:

 [...]


 You forgot an int in the arguments but otherwise that would 
 work fine with your line uncommented.


 yes I missed "int", but it's just an example.
 so if I'll write "this.property = value" it will work?


 I tested already and it really works, thank you.
 I asked that because I tried once to use "this" in past but I 
 got error. So I asked on some forum "how to get property of 
 class?" and peoples said that I may use just a name of 
 property. So I thought that there isn't "this" word.


Well "this" in D has different meanings as it depends on its 
context sometimes.
Nov 02 2016
parent Jonathan M Davis via Digitalmars-d-learn writes:
On Wednesday, November 02, 2016 07:26:57 Bauss via Digitalmars-d-learn 
wrote:

 Well "this" in D has different meanings as it depends on its
 context sometimes.


Yes, but it's almost always the same thing that you'd expect from a language
like C++ or Java.

- Jonathan M Davis
Nov 02 2016
prev sibling parent reply Jonathan M Davis via Digitalmars-d-learn writes:
On Wednesday, November 02, 2016 02:42:01 Konstantin Kutsevalov via 
Digitalmars-d-learn wrote:

 I tested already and it really works, thank you.
 I asked that because I tried once to use "this" in past but I got
 error. So I asked on some forum "how to get property of class?"
 and peoples said that I may use just a name of property. So I
 thought that there isn't "this" word.


I don't know why you were having trouble before, but I think that most
people never use an explicit this unless they need to, so plenty of folks
would have just told you to remove the this from you code, especially if it
worked without.

- Jonathan M Davis
Nov 02 2016
parent reply Steven Schveighoffer <schveiguy yahoo.com> writes:
On 11/2/16 4:43 AM, Jonathan M Davis via Digitalmars-d-learn wrote:

 On Wednesday, November 02, 2016 02:42:01 Konstantin Kutsevalov via
 Digitalmars-d-learn wrote:

 I tested already and it really works, thank you.
 I asked that because I tried once to use "this" in past but I got
 error. So I asked on some forum "how to get property of class?"
 and peoples said that I may use just a name of property. So I
 thought that there isn't "this" word.


 I don't know why you were having trouble before, but I think that most
 people never use an explicit this unless they need to, so plenty of folks
 would have just told you to remove the this from you code, especially if it
 worked without.


In the case of the original post, however, you *need* to use this.value, 
as the parameter masks the member of the same name. Using 'this' removes 
ambiguity.

This is a typical pattern seen in many languages. Often the intuitive 
name of a member is the same name as you want for the parameter of the 
constructor.

-Steve
Nov 03 2016
next sibling parent Jonathan M Davis via Digitalmars-d-learn writes:
On Thursday, November 03, 2016 09:40:11 Steven Schveighoffer via 
Digitalmars-d-learn wrote:

 On 11/2/16 4:43 AM, Jonathan M Davis via Digitalmars-d-learn wrote:

 On Wednesday, November 02, 2016 02:42:01 Konstantin Kutsevalov via

 Digitalmars-d-learn wrote:

 I tested already and it really works, thank you.
 I asked that because I tried once to use "this" in past but I got
 error. So I asked on some forum "how to get property of class?"
 and peoples said that I may use just a name of property. So I
 thought that there isn't "this" word.


 I don't know why you were having trouble before, but I think that most
 people never use an explicit this unless they need to, so plenty of
 folks
 would have just told you to remove the this from you code, especially if
 it worked without.


 In the case of the original post, however, you *need* to use this.value,
 as the parameter masks the member of the same name. Using 'this' removes
 ambiguity.

 This is a typical pattern seen in many languages. Often the intuitive
 name of a member is the same name as you want for the parameter of the
 constructor.


Yeah. That's the only reason that I ever use the this pointer/reference.

- Jonathan M Davis
Nov 03 2016
prev sibling parent Konstantin Kutsevalov <adamasantares gmail.com> writes:
On Thursday, 3 November 2016 at 13:40:11 UTC, Steven 
Schveighoffer wrote:

 On 11/2/16 4:43 AM, Jonathan M Davis via Digitalmars-d-learn

 In the case of the original post, however, you *need* to use 
 this.value, as the parameter masks the member of the same name. 
 Using 'this' removes ambiguity.

 This is a typical pattern seen in many languages. Often the 
 intuitive name of a member is the same name as you want for the 
 parameter of the constructor.

 -Steve


I'd like to use "this" because when I see something like 
"this.pumpurum = 10;" then I understand that "pumpurum" is 
property of class and not some local variable :)
Nov 04 2016