Getting the source code of a block

splattael · December 4, 2006, 12:22pm

Hello,

Is the following thing possible somehow?

def foo(&bar)
do_something_with(bar)
end

baz = foo { puts ‘hello’; i +=1; fluff(ork) }

now, baz should contain the string

“puts ‘hello’; i +=1; fluff(ork)”

since I need to do this in the same file where I am defining the block,
I could get it using FILE + some regexps - just asking if there is
some more elegant way…

TIA,
Peter
__
http://www.rubyrailways.com

splattael · December 4, 2006, 12:41pm

On 04.12.2006 12:20, Peter S. wrote:

“puts ‘hello’; i +=1; fluff(ork)”

since I need to do this in the same file where I am defining the block,
I could get it using FILE + some regexps - just asking if there is
some more elegant way…

No. Alternatively you could cook your own

irb(main):001:0> def pproc(code)
irb(main):002:1> block = eval(“lambda {#{code}}”)
irb(main):003:1> class <<block;self;end.send(:define_method,
:source_code) { code }
irb(main):004:1> block
irb(main):005:1> end
=> nil
irb(main):006:0> x = pproc ‘|a,b| a+b’
=> #Proc:0x003ba8bc@:1(eval)
irb(main):007:0> x[10,20]
=> 30
irb(main):008:0> x.source_code
=> “|a,b| a+b”

Where do you need that for?

Kind regards

robert

splattael · December 4, 2006, 1:07pm

Where do you need that for?

I am setting up a complicated object (similar to a tree) with this code:

crap = define_my_object do
foo do
bar
baz do
fluff :something => :hairy
ork :something => :other
end
end
end

now, I would like to call a few methods on ‘crap’ which will alter the
state of the object and eventually call a function which spits out crap
as:

crap = define_my_object do
foo do
bar :some => :new_param_here
baz do
fluff :now => :here, :are => :some, :other => things
ork :and => :even, :more => nil
end
end
end

I have been thinking about some kind of serialization which would be
certainly possible just by knowing crap - but since everything remains
the same except a few parameters, it seemed easier to me to
sub! (‘:something => :hairy’) {‘:now => :here, :are => :some, :other =>
things’} etc. - but for this I need the string of the original block of
course.

bw,
Peter

__
http://www.rubyrailways.com

splattael · December 4, 2006, 2:11pm

On 04.12.2006 13:06, Peter S. wrote:

       end
         fluff :now => :here, :are => :some, :other => things
         ork :and => :even, :more => nil
       end
     end
   end

So you are modifying the state of an object and want to emit code that
will recreate this state?

I have been thinking about some kind of serialization which would be
certainly possible just by knowing crap - but since everything remains
the same except a few parameters, it seemed easier to me to
sub! (’:something => :hairy’) {’:now => :here, :are => :some, :other =>
things’} etc. - but for this I need the string of the original block of
course.

I would rather go serialization - if you use YAML the serialized state
is actually human readable (sort of). Marshal is binary but also faster
IIRC. I would definitively go serialization if you want to store
configuration state between script executions.

Kind regards

robert

splattael · December 4, 2006, 3:19pm

I would rather go serialization - if you use YAML the serialized state
is actually human readable (sort of). Marshal is binary but also faster
IIRC. I would definitively go serialization if you want to store
configuration state between script executions.

Thanks for the answer. I guess to use yaml and maybe modify it a bit to
be even more human readable could be a meaningful compromise.

Cheers,
Peter

__
http://www.rubyrailways.com