Forum: Ruby Regular Expression Help

Hi, new to the forum, not new to Ruby but very new to Regular Expression
and they are killing me...

I have strings that look like this:
"--- this is a string ---" = "--- this is a string ---";
"  this is a string  " = "  this is a string  ";
"###this is a string" = "###this is a string";

I need to just get both string on each side to the equal sign, not
including the equal sign. I need to get all spaces or characters inside
the quotes but not including the quotes and not the semi-colon. I need
to compare the two strings. So...

this is a string this is a string

I tried using string.scan/regex/ which I like because it returns an
array. Again Fail.

I've tried all kinds of RegEx...I simply don't know what I'm doing and I
very frustrated. I have been using http://rubular.com/ to experiment but
I'm really not having success...

My most successful attempt, [^"=;] gets pretty much what I need but I
can't not select the space around the =.

I've looked at documentation, used Rubular and have tried a lot of
different things.

Can someone please help me?

Thanks

Brad

Am 06.10.2012 01:11, schrieb Brad Askins:
> the quotes but not including the quotes and not the semi-colon. I need
>
> My most successful attempt, [^"=;] gets pretty much what I need but I
> can't not select the space around the =.

1.9.3-p194 :001 > text = '"--- this is a string ---" = "--- this is a
string ---";'
  => "\"--- this is a string ---\" = \"--- this is a string ---\";"
1.9.3-p194 :002 > text.scan(/"(.*?)" = "(.*?)"/).flatten
  => ["--- this is a string ---", "--- this is a string ---"]

On Sat, Oct 6, 2012 at 1:21 AM,  <sto.mar@web.de> wrote:

> 1.9.3-p194 :001 > text = '"--- this is a string ---" = "--- this is a string
> ---";'
>  => "\"--- this is a string ---\" = \"--- this is a string ---\";"
> 1.9.3-p194 :002 > text.scan(/"(.*?)" = "(.*?)"/).flatten
>  => ["--- this is a string ---", "--- this is a string ---"]

I'd rather use an approach which explicitly includes the "=" sign, for 
example

irb(main):026:0> text = '"--- this is a string ---" = "--- this is a
string ---";'
=> "\"--- this is a string ---\" = \"--- this is a string ---\";"
irb(main):027:0> if %r{"([^"]*)"\s*=\s*"([^"]*)"} =~ text then p $1, $2 
end
"--- this is a string ---"
"--- this is a string ---"
=> ["--- this is a string ---", "--- this is a string ---"]

If one wants to allow escaped quotes inside the string things get a
bit more tricky but that's doable as well:

irb(main):028:0> text = '"--- this is an escaped quote: \"" = "---
this is a string ---";'
=> "\"--- this is an escaped quote: \\\"\" = \"--- this is a string 
---\";"
irb(main):029:0> if %r{"((?:\\.|[^"\\])*)"\s*=\s*"((?:\\.|[^"\\])*)"}
=~ text then p $1, $2 end
"--- this is an escaped quote: \\\""
"--- this is a string ---"
=> ["--- this is an escaped quote: \\\"", "--- this is a string ---"]

Of course, you could also include the trailing ";" in the match to be
even more restrictive.

irb(main):030:0> if
%r{"((?:\\.|[^"\\])*)"\s*=\s*"((?:\\.|[^"\\])*)"\s*;} =~ text then p
$1, $2 end
"--- this is an escaped quote: \\\""
"--- this is a string ---"
=> ["--- this is an escaped quote: \\\"", "--- this is a string ---"]

Kind regards

robert

Am 06.10.2012 12:12, schrieb Robert Klemme:
> On Sat, Oct 6, 2012 at 1:21 AM,  <sto.mar@web.de> wrote:
>
>> 1.9.3-p194 :001 > text = '"--- this is a string ---" = "--- this is a string
>> ---";'
>>   => "\"--- this is a string ---\" = \"--- this is a string ---\";"
>> 1.9.3-p194 :002 > text.scan(/"(.*?)" = "(.*?)"/).flatten
>>   => ["--- this is a string ---", "--- this is a string ---"]
>
> I'd rather use an approach which explicitly includes the "=" sign

???

It does.

On Sat, Oct 6, 2012 at 12:25 PM,  <sto.mar@web.de> wrote:
>>
>> I'd rather use an approach which explicitly includes the "=" sign
>
> ???
>
> It does.

Right you are.  I let myself irritate by your usage of String#scan.
Sorry for that.

I do not think this is a case for #scan though since according to the
OP's description the String only contains one "assignment".  So it's
either "match" or "don't match".

Kind regards

robert

text.scan(/"(.*?)" = "(.*?)"/).flatten

That worked awesome!!

So I was getting pretty close. I see what I was doing wrong now that I
see the solution.

That's for your help.

I need more practice on RegEx.

Thanks again.

Brad