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From: vardhan patil on 4 Aug 2010 04:42
Me using the latest version of gem win32screen shot..
But while taking desktop screenshot i get undefined method `call for
nil:NilClass
for capture_area in bitmap maker.rb line 159
bitmap maker.rb line 127
and screenshot.rb line 29

Plz help
From: Roger Pack on 4 Aug 2010 10:54
vardhan patil wrote:
> Me using the latest version of gem win32screen shot..
> But while taking desktop screenshot i get undefined method `call for
> nil:NilClass
> for capture_area in bitmap maker.rb line 159
> bitmap maker.rb line 127
> and screenshot.rb line 29
>
> Plz help

You need to pass it a block, like the readme examples do.

http://github.com/jarmo/win32screenshot
--
Posted via http://www.ruby-forum.com/.

From: Jarmo Pertman on 7 Aug 2010 06:39
Maybe using yield might be better indeed, like Roger recommended some
time ago. It seems that this named block variable doesn't help much as
i hoped. Too bad that Ruby won't throw error or show warning if named
block variables are used but no block given... for me it's like x
parameters are needed, but x-1 parameters given and there's no default
value for block so error should be shown like it is done with other
cases where more or less parameters are given to the method than
expected.

Jarmo

On Aug 4, 5:54 pm, Roger Pack <rogerpack2...(a)gmail.com> wrote:
> vardhan patil wrote:
> > Me using the latest version of gem win32screen shot..
> > But while taking desktop screenshot i get undefined method `call for
> > nil:NilClass
> > for capture_area in bitmap maker.rb line 159
> > bitmap maker.rb line 127
> > and screenshot.rb line 29
>
> > Plz help
>
> You need to pass it a block, like the readme examples do.
>
> http://github.com/jarmo/win32screenshot
> --
> Posted viahttp://www.ruby-forum.com/.

From: Roger Pack on 7 Aug 2010 08:01
> Too bad that Ruby won't throw error or show warning if named
> block variables are used but no block given... for me it's like x
> parameters are needed, but x-1 parameters given and there's no default
> value for block so error should be shown like it is done with other
> cases where more or less parameters are given to the method than
> expected.

Yeah the only way I know of to force their use it so either use yield
(which will throw a LocalJumpError: no block given), or to raise like

raise LocalJumpError.new unless block
or
raise LocalJumpError.new unless block_given? (handle the implicit case)

I wonder if there's some other way, as well, that I don't know about.
--
Posted via http://www.ruby-forum.com/.

From: Jarmo Pertman on 8 Aug 2010 17:17
Released version 0.0.6 where i'm using yield instead of block.call.
Hopefully it makes it more clear that block needs to be used :)

Jarmo

On Aug 7, 3:01 pm, Roger Pack <rogerpack2...(a)gmail.com> wrote:
> > Too bad that Ruby won't throw error or show warning if named
> > block variables are used but no block given... for me it's like x
> > parameters are needed, but x-1 parameters given and there's no default
> > value for block so error should be shown like it is done with other
> > cases where more or less parameters are given to the method than
> > expected.
>
> Yeah the only way I know of to force their use it so either use yield
> (which will throw a LocalJumpError: no block given), or to raise like
>
> raise LocalJumpError.new unless block
> or
> raise LocalJumpError.new unless block_given? (handle the implicit case)
>
> I wonder if there's some other way, as well, that I don't know about.
> --
> Posted viahttp://www.ruby-forum.com/.

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