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On Sun, 05 Feb 2006 02:49:58 -0000, Schüle Daniel
<> wrote:

> irb(main):005:0* cnt=0
> => 0
> irb(main):006:0> cc=nil
> => nil
> irb(main):007:0> callcc {|cc|}
> => nil
> irb(main):008:0> cnt+=1
> => 1
> irb(main):009:0> cc.call if cnt < 10
> => nil
> irb(main):010:0> cnt
> => 1
> irb(main):011:0>
> irb(main):012:0* RUBY_VERSION
> => "1.8.4"
> irb(main):013:0>
>
> this example is from
> http://www.rubygarden.org/ruby?Continuations
> and cnt should become 10
>

I've found that certain things like continuations don't work well under
IRB. I think it's because of the way it's workspaces work.

That code works fine as a script.

--
Ross Bamford -

[Sch=FCle Daniel <>, 2006-02-05 01.58 CET]
> Hello,
>=20
> irb(main):005:0* cnt=3D0
> =3D> 0
> irb(main):006:0> cc=3Dnil
> =3D> nil
> irb(main):007:0> callcc {|cc|}
> =3D> nil
> irb(main):008:0> cnt+=3D1
> =3D> 1
> irb(main):009:0> cc.call if cnt < 10
> =3D> nil
> irb(main):010:0> cnt
> =3D> 1
> irb(main):011:0>
> irb(main):012:0* RUBY_VERSION
> =3D> "1.8.4"
> irb(main):013:0>
>=20
> this example is from
> http://www.rubygarden.org/ruby?Continuations
> and cnt should become 10

The problem is IRB. It is a ruby program whose main loop reads your input=
,
evaluates it, and shows you the result, so when you call the continuation=
,
it only returns to the point where it shows you the result of your input;
it doesn't evaluate the statementes you entered later.

Try the example outside IRB.

--=20

Hello,

irb(main):005:0* cnt=0
=> 0
irb(main):006:0> cc=nil
=> nil
irb(main):007:0> callcc {|cc|}
=> nil
irb(main):008:0> cnt+=1
=> 1
irb(main):009:0> cc.call if cnt < 10
=> nil
irb(main):010:0> cnt
=> 1
irb(main):011:0>
irb(main):012:0* RUBY_VERSION
=> "1.8.4"
irb(main):013:0>

this example is from
http://www.rubygarden.org/ruby?Continuations
and cnt should become 10

I also tried some other examples from the net
and it worked only in this case

irb(main):014:0* callcc do |cc|
irb(main):015:1* for i in 0..10
irb(main):016:2> print "\n#{i}: "
irb(main):017:2> for j in 0..10
irb(main):018:3> cc.call if j == 5 and i == 5
irb(main):019:3> printf "%3i", j
irb(main):020:3> end
irb(main):021:2> end
irb(main):022:1> end

0: 0 1 2 3 4 5 6 7 8 9 10
1: 0 1 2 3 4 5 6 7 8 9 10
2: 0 1 2 3 4 5 6 7 8 9 10
3: 0 1 2 3 4 5 6 7 8 9 10
4: 0 1 2 3 4 5 6 7 8 9 10
5: 0 1 2 3 4=> nil
irb(main):023:0>

Maybe someone can help

Regards, Daniel