From: Rasputin <rasputnik@...>
Date: 2004-01-06T21:01:55+09:00
Subject: Re: proc question and instance_methods

Jamis Buck wrote:

> GGarramuno wrote:
>
>> 1) I assume the question will be no, but is it possible to evaluate a
>> piece of proc code for syntax errors?  That is, I have a construct of
>> the form:
>>
>>       text = "some text coming from somewhere"
>>       code = proc { text }
>>
>> I'd like to know whether text is valid ruby code (syntactically),
>> without having to run the proc.  In perl, this would be done by
>> running eval on the code, as perl compiles to bytecode the proc even
>> if not running it.
>> But in ruby, it seems the proc is not "compiled" until run.  Is there
>> any work-around for this?
>
> If you pass the code to eval, you can then test for a SyntaxError 
> exception, like so:
>
>  text = "some text coming from somewhere"
>  begin
>     eval "text"
>  rescue SyntaxError => e
>     # do something when it has a syntax error
>  end
>  

But that would execute the code, wouldn't it?