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Newsgroups: comp.lang.ruby
Date: Thu, 5 Jul 2018 09:10:51 -0700 (PDT)
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Subject: Re: Ultimate Guide to Ruby Strings
From: Robert Klemme <shortcutter@googlemail.com>
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Xref: csiph.com comp.lang.ruby:7395

On Sunday, February 4, 2018 at 7:00:17 PM UTC+1, Jesus Castello wrote:
> Hello!
> I wrote an article about ruby string methods on my blog rubyguides.
> 
> You can read it here:
> 
> http://www.rubyguides.com/2018/01/ruby-string-methods/
> 
> Let me know what you think :)

Looks good.  Just a few minor nitpicks:

My preferred method to test whether a string represents a number is to actually convert it and deal with the error:

begin
  i = Integer(str)
  printf "%d\n", i
rescue ArgumentError
  puts "Oh, it's not a number!"
end

Or

i = Integer(str) rescue nil

if i ...



There is another way to extract a sub string:

substr = str[/fo+/]

and for replacing parts of the string:

str[/fo+/] = "bar"

(You'll get an IndexError if there is no match.)

Cheers

robert