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digitalmars.D.bugs - [Issue 11733] New: Refuse int indexing of associative arrays with char keys

reply d-bugmail puremagic.com writes:
https://d.puremagic.com/issues/show_bug.cgi?id=11733

           Summary: Refuse int indexing of associative arrays with char
                    keys
           Product: D
           Version: D2
          Platform: x86
        OS/Version: Windows
            Status: NEW
          Keywords: accepts-invalid
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: nobody puremagic.com
        ReportedBy: bearophile_hugs eml.cc



I think this code should be disallowed:


void main() {
    int[char] aa1;
    int[dchar] aa2;
    auto r1 = aa1[0];
    auto r2 = aa2[0];
}


dmd 2.065alpha compiles it with no errors, and gives at run-time:

core.exception.RangeError temp(4): Range violation

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next sibling parent d-bugmail puremagic.com writes:
https://d.puremagic.com/issues/show_bug.cgi?id=11733


yebblies <yebblies gmail.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |yebblies gmail.com



Why?  0 implicitly converts to both char and dchar.

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prev sibling next sibling parent d-bugmail puremagic.com writes:
https://d.puremagic.com/issues/show_bug.cgi?id=11733


bearophile_hugs eml.cc changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |minor



This is not as important as other changes I have proposed elsewhere.




 Why?  0 implicitly converts to both char and dchar.


Because int and char are two different types. It makes code less clear, and in
D there is a simple syntax to express that:

auto r1 = aa1['\0'];
auto r2 = aa2['\0'];

There is no ambiguity here, '\0' is clearly a char for the person that reads
the code. Using 0 instead of '\0' seems a weakly typing archaism coming from C.

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Dec 13 2013
prev sibling parent d-bugmail puremagic.com writes:
https://d.puremagic.com/issues/show_bug.cgi?id=11733


yebblies <yebblies gmail.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Platform|x86                         |All
         OS/Version|Windows                     |All
           Severity|minor                       |enhancement



There is no ambiguity anyway.  Asking for int not to convert to char is not
new, and I vaguely recall it was rejected on the grounds that char x = 'a'+7;
should work.  I don't if there is an existing report for that.

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