Quick question regarding dynamic array deletions

Dennis dkorpel at gmail.com
Sun Sep 1 18:42:54 UTC 2019


On Sunday, 1 September 2019 at 18:26:20 UTC, WhatMeWorry wrote:
> Maybe my question is when would be want to use 3) without also 
> adjusting the .ptr ?

It matters when casting to a boolean, since an empty array with a 
non-null pointer is still `true` while an array with null pointer 
casts to `false`. This could be useful when you want to 
distinguish 'no array' and an empty array.

For example:
```
int[] getList(); // might fail

void main() {
   if (auto list = getList) {
     writeln(list); // could be an empty list
   } else {
     error("could not retrieve list"); // must be 'null' list
   }
}
```




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