Duplicate keys in array literals?

[bearophile]

Is it a good idea to silently statically accept duplicated keys 
in both dynamic array literals and in associative array literals?



void main() {
int[] a = [0:10, 0:20];
int[int] aa = [0:10, 0:20];
}


I don't remember having ever had the need for this, and on the 
other hand I have had some mistakes like this in my D code not 
caught statically by the compiler.


---

Note that in this post I am not discussing about inserting 
multiple times a key-pair in an associative array, this is normal 
and useful:


void main() {
int[int] aa;
aa[0] = 10;
aa[0] = 20;
}

Bye,
bearophile

Re: Duplicate keys in array literals?

[Daniel Murphy]

bearophile bearophileh...@lycos.com wrote in message 
news:befwnwpitihpcjfbd...@forum.dlang.org...
 Is it a good idea to silently statically accept duplicated keys in both 
 dynamic array literals and in associative array literals?


Looks like a bug to me. 

Re: Duplicate keys in array literals?

[luka8088]

On 28.11.2013. 12:23, bearophile wrote:
 Is it a good idea to silently statically accept duplicated keys in both
 dynamic array literals and in associative array literals?
 
 
 void main() {
 int[] a = [0:10, 0:20];
 int[int] aa = [0:10, 0:20];
 }
 
 
 I don't remember having ever had the need for this, and on the other
 hand I have had some mistakes like this in my D code not caught
 statically by the compiler.
 
 ---
 
 Note that in this post I am not discussing about inserting multiple
 times a key-pair in an associative array, this is normal and useful:
 
 void main() {
 int[int] aa;
 aa[0] = 10;
 aa[0] = 20;
 }
 
 Bye,
 bearophile

PHP also allows it:

$data = array('a' = 1, 'a' = 2);

And I find it to be only a source of bugs.

Re: Duplicate keys in array literals?

[Denis Shelomovskij]

28.11.2013 15:23, bearophile пишет:

Is it a good idea to silently statically accept duplicated keys in both
dynamic array literals and in associative array literals?


void main() {
 int[] a = [0:10, 0:20];
 int[int] aa = [0:10, 0:20];
}


I don't remember having ever had the need for this, and on the other
hand I have had some mistakes like this in my D code not caught
statically by the compiler.

---

Note that in this post I am not discussing about inserting multiple
times a key-pair in an associative array, this is normal and useful:

void main() {
 int[int] aa;
 aa[0] = 10;
 aa[0] = 20;
}

Bye,
bearophile


File the issue please.

--
Денис В. Шеломовский
Denis V. Shelomovskij

Re: Duplicate keys in array literals?

[Jacob Carlborg]

On 2013-11-28 18:55, luka8088 wrote:


PHP also allows it:

$data = array('a' = 1, 'a' = 2);

And I find it to be only a source of bugs.


Arrays are a weird beast in PHP. They're both arrays and associative 
arrays, at the same time, somehow.


--
/Jacob Carlborg

Re: Duplicate keys in array literals?

[luka8088]

On 28.11.2013. 21:01, Jacob Carlborg wrote:
 On 2013-11-28 18:55, luka8088 wrote:
 
 PHP also allows it:

 $data = array('a' = 1, 'a' = 2);

 And I find it to be only a source of bugs.
 
 Arrays are a weird beast in PHP. They're both arrays and associative
 arrays, at the same time, somehow.
 

They are associative array which can emulate array like behavior. But
unfortunately that has also in my experience turned out to be just
another source of bugs.

Re: Duplicate keys in array literals?

[bearophile]

Denis Shelomovskij:


File the issue please.


I have opened an issue, currently it's not an enhancement request:
https://d.puremagic.com/issues/show_bug.cgi?id=11637

In that issue I have also added more explanations and more code 
examples, with an extra small discussion about arrays with 
strongly typed indexes, that I have never stopped missing in D, 
being used to them since Delphi.


Bye,
bearophile