[ruby-core:34684] Re: Returning from the callee

  Em 20-01-2011 18:51, Nikolai Weibull escreveu:
> On Thu, Jan 20, 2011 at 19:27, Rodrigo Rosenfeld Rosas
> <[e-mail]>  wrote:
>
>> return nil.tap { render text: 'failed' } unless request.valid?
> unless request.valid?
>    render text: 'failed'
>    return nil
> end
> …
>
> or
>
> if request.valid?
>    …
> else
>    render text: 'failed'
>    nil
> end
>
> or
>
> return render_failure unless request.valid?
> …
>
> def render_failure
>    render text: 'failed'
>    nil
> end
>
> The example you keep giving seems to have its problems stem from
> poorly factored code, not the lack of non-local exits

What I really want is a simple way for doing simple things. I usually 
use a one-line code for a simple statement like this because it makes 
easier for me for reading the code.

If it was possible to write

render text: 'failed' unless request.valid?
...
render 'template/output'

, why would I have to write things like the code below?

unless request.valid?
     render text: 'failed' unless request.valid?
     return
end
...
render 'template/output

I don't want to give focus on special case error handling but on the 
usual case instead.

Currently, it is possible to write something like:

return(render(text: 'invalid')) unless request.valid?

But I don't like this approach because it seems we are really interested 
in the result value, when we are not.

The "return nil.tap{}" approach was just an attempt to show how people 
could write code in a one-line statement for achieving this goal with 
Ruby, currently. I mean, I didn't see anyone writing code like this, but 
I don't doubt someone could be tempted to write this kind of code if 
they don't want to use 3 extra unnecessary lines giving extra focus to 
any special error handling cases instead of the really interesting part 
of the code.

Ruby is all about being expressive while coding. At least, that is the 
main reason I like Ruby. I really don't like boilerplate code.

Rodrigo.