From: Ezra Zygmuntowicz <ezra@...>
Date: 2005-08-10T01:15:02+09:00
Subject: Re: Re-reading a portion of a source file from a specific point


On Aug 9, 2005, at 8:14 AM, Berger, Daniel wrote:

> Hi all,
>
>
>> From within a Ruby program, is there a way to get Ruby to re-read  
>> itself
>>
> from a specific part of the file?  Let me explain.  Say I have a  
> method
> "foo".  I would like "foo" to slurp the rest of the script into memory
> and write it to a file, possibly a temp file.
>
> For example:
>
> 1: puts "Hello World"
> 2: foo()
> 3: puts "How's it going?"
>
> In this script I would like lines 2 and 3 (or possibly just line 3  
> - I'm
> not sure yet), but NOT line 1, read into memory and written to a file
> (by the foo method).  I thought perhaps there were some tricks I could
> use with __DATA__, __END__ or __FILE__, but I wasn't sure.
>
> Any ideas?
>
> Regards,
>
> Dan
>
>
>
>
>

There is an obscure constant called SCRIPT_LINES__ . To use it you  
would have to put the script that you want to have access to in a  
file and include it in another. Like so:

-----test.rb--------
a= "Hello World"
b = "Foo Bar"
c = "How's it going?"
d = "Another Line"
------end test.rb------

------main.rb-------
SCRIPT_LINES__ = {}
require 'test'
p SCRIPT_LINES__
p SCRIPT_LINES__.keys
-----end main.rb--------

Result:
ezra:~/Sites ez$ ruby main.rb
{"./main.rb"=>["a= \"Hello World\"\n", "b = \"Foo Bar\"\n", "c =  
\"How's it going?\"\n", "d = \"Another Line\""]}
------------
["./main.rb"]

     So after you do this, you will have a hash that contains arrays  
of every line in every file you require, keyed by the file name of  
the required file. Kind of wierd but I think you could use this to do  
what you want to do.

HTH-
-Ezra Zygmuntowicz
Yakima Herald-Republic
WebMaster
509-577-7732
ezra@yakima-herald.com