Rather nasty bug that silently fails. Linux DMD64 D Compiler v2.065

import std.stdio;
import std.array;
import std.conv;
import std.digest.crc;
import std.random;

class Foo
{
	public string generateHash()
	{
		// The following variable is untyped
		// yet no compiler error is thrown.
		text = Random(unpredictableSeed).front.to!(string);

		// text is null here.
		return hexDigest!(CRC32)(text).array.to!(string);
	}
}

void main(string[] args)
{
	auto foo = new Foo();

	writefln("%s", foo.generateHash());
}

Reported: https://d.puremagic.com/issues/show_bug.cgi?id=12357

On Thursday, 13 March 2014 at 13:57:49 UTC, Gary Willoughby wrote:
> 		text = Random(unpredictableSeed).front.to!(string);

This is actually calling the function std.conv.text.... this line is rewritten to:

std.conv.text(Random(unpredictableSeed).front.to!(string));

The text function converts all is arguments to string and returns them all concated together.

It thinks you are trying to use a property setter.

> 		// text is null here.
> 		return hexDigest!(CRC32)(text).array.to!(string);

And here, it is calling the text function with no arguments and no parens (similarly to a property getter). With no arguments, it just returns null.




So this isn't actually a bug, D is working as designed, but it is a better example than the common "writeln = 1;" thing given in most property setter arguments...

On 3/13/14, Gary Willoughby <dev@nomad.so> wrote:
> Rather nasty bug that silently fails. Linux DMD64 D Compiler v2.065

Unfortunately it's not a variable, it's the std.conv.text function being called. I've actually ran into this nasty "bug" once already.

It all boils down to being allowed to call functions via "foo = bar;"

-----
void text(string x) { }

void main()
{
    text = "";
}
-----

However I think this will be finally fixed once property enforcement is properly implemented.

On Thursday, 13 March 2014 at 14:07:22 UTC, Adam D. Ruppe wrote:
> On Thursday, 13 March 2014 at 13:57:49 UTC, Gary Willoughby wrote:
>> 		text = Random(unpredictableSeed).front.to!(string);
>
> This is actually calling the function std.conv.text.... this line is rewritten to:
>
> std.conv.text(Random(unpredictableSeed).front.to!(string));
>
> The text function converts all is arguments to string and returns them all concated together.
>
> It thinks you are trying to use a property setter.
>
>> 		// text is null here.
>> 		return hexDigest!(CRC32)(text).array.to!(string);
>
> And here, it is calling the text function with no arguments and no parens (similarly to a property getter). With no arguments, it just returns null.
>
>
>
>
> So this isn't actually a bug, D is working as designed, but it is a better example than the common "writeln = 1;" thing given in most property setter arguments...

Ah yes of course!