Re: Regular Expression question

On 6/30/07, Peter Seebach <seebs@xxxxxxxxx> wrote:
In message <0df4a451b19810ff6e06f11725324591@xxxxxxxxxxxxxx>, Al Cholic writes:
>Im working with regular expressions and I cant quite understand how the
>"13" is extracted from the string.
>Here is the irb output:
>irb(main):005:0> "(13)"[1..-2].to_i
>=> 13
>I dont understadn how the [1..-2] parameter removes the parenthases from
>the string.

"(13)"[0] = "("
"(13)"[1] = "1"
"(13)"[2] = "3"
"(13)"[3] = ")"

"(13)"[-1] = ")"
"(13)"[-2] = "3"
"(13)"[-3] = "1"
"(13)"[-4] = "("
Maybe it would not hurt to add a little clarification, albeit the fact
that your didactic simplification has worked very well :). Especially
as this concerns a FAQ

In reality
"(13)"[0] => ?( which equals 40
and
"(13)"[0..0] => "("

Cheers
Robert
--
I always knew that one day Smalltalk would replace Java.
I just didn't know it would be called Ruby
-- Kent Beck

.

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