From: james@...
Date: 2002-03-26T23:23:54+09:00
Subject: RE: Difference between 'do' and 'begin'



> -----Original Message-----
> From: Clemens Hintze [mailto:c.hintze@gmx.net]

<snip />

> Although there *are* two 'keywords' to open a block, but those are
> 'do' and '{'. Both have different precedence, so that both following
> lines have different meaning:
>
...
<snip/>

>
> 'begin' is a totally different construct, that is *not* building a
> block. It is more a statement like 'if' or 'while' ...
>
> - A block, e.g., can be converted into a closure. You cannot do this
>   with 'begin' started code.
> - A block opens an own scope for variables that were created within
>   the block. And it reuse variables that were created outside. 'begin'
>   do *not* open a new scope. All variables crated within are
>   accessible outside.
>
> 'begin' is most often used together with its 'rescue' and/or 'ensure'
> part to catch and handle exceptions that were raised by code within.


However, both Ruby in a Nutshell and the Pickaxe book refer to begin/end as
blocks.
So, is it incorrect to refer to

  begin
    # some code
  end

as a block?

Or is it block, but not the same sort of block as:

  { |foo|
    # do something with foo
  }

James



>
> Regards,
> \cle
> --
> Clemens Hintze  mailto: c.hintze@gmx.net
>