From: "Brian Schröder" <ruby.brian@...>
Date: 2005-06-01T20:42:53+09:00
Subject: Re: array of object insert polices

On 01/06/05, dave <dave.m@email.it> wrote:
> 
> 
> > You should have a look at the thread:
> > Uniform vector class, inheriting from Array
> 
> > Duck typing. Code that relies on ints in there will soon discover if
> > someone puts something non numeric in there.
> 
> I had a look at Chapter 23 Duck Typing of Programming Ruby.
> 
> I understand that i haven't to validate imput type, this let me
> a little bit lost.
> 
> >"Code that relies on ints will discover"
> ..and what if i write a class to calculate a productory and who uses
> this class see something like that on the monitor:
> 
> "i'm an integer Hahhaaai'm an integer Hahhaaai'm an integer Hahhaaai'm an
> integer Hahhaaai'm an integer Hahhaaai'm an integer Hahhaaai'm an integer
> Hahhaaai'm an integer Hahhaaai'm an integer Hahhaaa"
> 
> (he wronged to parse an imput file `integers: 3 3`).
> 
> maybe unit tests can help me?
> 
> help me, please.
> 
> 

If you parse string input that should be converted to int you would
normally validate the input. Take for example a look at the highline
library for this purpose.

And what should the unit do if it is used in a wrong way? Throwing and
exception is normally a good idea. And this can be achieved simple by
method missing errors.

best regards,

Brian



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