From: Isaac Gouy <igouy@...>
Date: 2006-01-10T07:13:03+09:00
Subject: Re: Ideas on "Why Living Dangerous can be A Good Thing" in Ruby?


Eivind Eklund wrote:
> On 1/9/06, Isaac Gouy <igouy@yahoo.com> wrote:
> > Eivind Eklund wrote:
> > > At this cost, the type and variable declarations had better give us a
> > > lot.  In practice, I find that they give me very little, bug wise:
> > > Maybe 5% of my simplest bugs are detected by them.  The advantages I
> > > get are in the speed of the compiled code, and as documentation.
> > > However, these benefits are too small to be worthwhile for the size
> > > projects I presently do (one and two person projects).
> >
> > Does a language with type-inference require as many type and variable
> > declarations as a language without type-inference?
>
> Does a reference to declaring types and variables make it clear to you
> that we're talking about a language where you have to declare types
> and variables, and *not* one based on type inference?

No

>
> > Is the C++ type system the same as the SML type system?
>
> Does the SML type system include declaring types and variables to the
> degree of taking up roughly half the code?
>

Depends how you write it

> > Will programmers who passively suffer compiler type-checking detect as
> > many bugs as programmers who actively use 'type-full' programming as a
> > checking-tool?
>
> Will people that use the annoying technique of asking bad rethorical
> questions get on your nerves too?
>
> ;)
>

Not as much as those who make wild generalizations ;-)


> Really, and in all friendliness, the question isn't if they'll detect
> as many bugs.  The question is if those that tries to use types as a
> checking tool find so many bugs and/or get so many other benefits that
> the costs introduced by the types are worth it.  The answer will vary
> by language, by environment, by programmer, and by methodology used.
> I believe the static type system of SML or Haskell may well be worth
> it - I've just not worked enough with it to know.
>
> For me, in the environment I work in, with the ways I work with Ruby,
> I've found that very few of my bugs would be caught by extra type
> checking.  I just don't end up with wrongly typed data much at all,
> and in the few cases where I do, the errors have come up immediately.
> Since I wrote my type checking library, I've not had a subtle bug that
> would be caught by more type checking.  Before I wrote the type
> checking library, I thought that adding more type checking would catch
> a significant amount of bugs.  When I added more type checking and
> found that it got in the way, I started looking for cases where it
> would have helped.  I found very few, and they've so far shown up
> immediately (as methods missing).
> 
> Eivind.