From: Phlip <phlip2005@...>
Date: 2007-09-26T02:05:10+09:00
Subject: Re: so surprised syntax error not caught here

SpringFlowers AutumnMoon wrote:

>  the following syntax error for "elif" is not caught?  (should be elsif)
>
> def foo(i)
>   if i < 0
>     return "Less than 0"
>   elif i == 0
>     return "it is zero"

Ruby is interpretive; it does not link all its symbols to real
entities at compile time. (Unlike certain other languages we could
mention.

elif could be a function that takes a boolean. Ruby can't know this
until it interprets the line, because you might have used eval() or
something to create that function before getting here.

In exchange for a lot more flexibility, Ruby does fewer sanity checks
at parse time.

To keep Ruby on track, and catch errors like this, all Ruby developers
should write unit tests for everything.

-- 
 Phlip