Interview at Lang.NEXT

[Adam D. Ruppe via Digitalmars-d-announce]

On Wednesday, 4 June 2014 at 21:02:21 UTC, Craig Dillabaugh wrote:
> However, my primary point was that adding a string to a number
> is really an 'undefined' operation.  So I don't think such
> automatic casting is (generally) helpful.

Yeah, I'm generally against it... but I have a weird view of 
typing.

The way I see it, you should go either strong and static or 
dynamic and weak - I hate the middle ground.

So, in my view:

Best (like D):
string a = "10"; int b = 20;
a + b; // compile time error: cannot do string + int

Sometimes ok (my jsvar/script language also PHP and some others):
var a = "10"; var b = 20;
a + b; // 30

Blargh (javascript):
var a = "10"; var b = 20;
a + b; // "1020"

Hatred:
var a = "10"; var b = 20;
a + b; // throws an exception at run time



The D one is best because it draws your attention to something 
that is imperfect immediately and reliably via a compilation 
error. Then you can solve it with to!int or
whatever easily.

The weak+dynamic is passable to me because it actually mostly 
works. The operator you choose coerces the arguments and gives 
something basically usable. I'd be ok if it
threw an exception in the case of a string that cannot be sanely 
converted to int, but if it can be made to work, just do it.

The javascript one is blargh just because + is overloaded, making 
it easy to accidentally do the wrong thing (this just bit me in a 
real world code thing like 20
minutes ago, coincidentally). But I still prefer it to the last 
one..

Which cares about the types enough to throw an exception, but 
makes you wait for runtime to tell you about it. Pain in the butt 
that leads to fragile code that just
breaks a lot.


For example, one version of a library returns numbers typed as 
strings so you do some string stuff on them... then the next 
version returns them typed as numbers and
the old string concat pieces now randomly break next time you run 
it.

Pain! If I need to know what the type is anyway, please just give 
me a compiler to catch this stuff.

Alas, the latter model is what Ruby and Python do :(