From: "David A. Black" <dblack@...>
Date: 2009-07-23T10:43:07+09:00
Subject: Re: Question about text parsing

Hi --

On Thu, 23 Jul 2009, spox wrote:

> On Wednesday 22 July 2009 14:58:47 Stephen Beard wrote:
>> Hello,
>>
>> I am new to ruby and had a question about parsing text.
>>
>> I am trying to parse out the first IP address from a string. I have a
>> working solution, but it seems like a rather round about way to do it.
>> This is my current method:
>>
>> str = "          inet addr:192.168.1.118  Bcast:192.168.1.255
>> Mask:255.255.255.0"
>> ipAddr = ((str.split(':'))[1].split)[0]
>>
>> Is there a better way to do this? Thanks in advance.
>
> regexp:
> str.scan(/addr:([^\s]+)/)[0][0]
>
> string math:
> str.slice(str.index(':')+1, str.index(' B')-str.index(':')-2)

Here's a technique involving subscripting a string with a regular
expressions. The number 1 at the end causes the whole thing to return
the contents of the first parenthetical capture (which is all
consecutive non-space characters following the first colon).

str[/:(\S+)/,1]


David

-- 
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