Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.ruby > #3469 > unrolled thread

Replace any multiple whitespaces with single white space

Back to article view | Back to comp.lang.ruby

Contents

  Replace any multiple whitespaces with single white space Michelle Pace <michelle@michellepace.com> - 2011-04-25 13:44 -0500
    Re: Replace any multiple whitespaces with single white space Joel VanderWerf <joelvanderwerf@gmail.com> - 2011-04-25 13:51 -0500
      Re: Replace any multiple whitespaces with single white space Josh Cheek <josh.cheek@gmail.com> - 2011-04-25 14:02 -0500
        Re: Replace any multiple whitespaces with single white space Joel VanderWerf <joelvanderwerf@gmail.com> - 2011-04-25 14:14 -0500
          Re: Replace any multiple whitespaces with single white space Gunther Diemant <g.diemant@gmx.net> - 2011-04-25 15:43 -0500
      Re: Replace any multiple whitespaces with single white space Brian Candler <b.candler@pobox.com> - 2011-04-26 07:03 -0500
        Re: Replace any multiple whitespaces with single white space Joel VanderWerf <joelvanderwerf@gmail.com> - 2011-04-26 11:27 -0500
        Re: Replace any multiple whitespaces with single white space Joel VanderWerf <joelvanderwerf@gmail.com> - 2011-04-26 11:31 -0500
    Re: Replace any multiple whitespaces with single white space John W Higgins <wishdev@gmail.com> - 2011-04-25 13:56 -0500
    Re: Replace any multiple whitespaces with single white space Alexander McMillan <alexandermcmillan@hotmail.com> - 2011-04-26 05:18 -0500

#3469 — Replace any multiple whitespaces with single white space

Hello, I need to make the first string below into the second string.
That is, only single white spaces are permitted.

"1/4 WELDING    LEVER FRONT DRW 14844-C  MAT  WMA1CM-WLFRONT"
into
"1/4 WELDING LEVER FRONT DRW 14844-C MAT WMA1CM-WLFRONT"



I want to use the sub! method. Why does the below code not work? Is my
pattern incorrect?

descrip = "1/4 WELDING    LEVER FRONT DRW 14844-C  MAT  WMA1CM-WLFRONT"
descrip.sub!(/\s+/,' ')
puts descrip



Thank-you in advance,
Michelle

-- 
Posted via http://www.ruby-forum.com/.

[toc] | [next] | [standalone]

#3470

On 04/25/2011 11:44 AM, Michelle Pace wrote:
> Hello, I need to make the first string below into the second string.
> That is, only single white spaces are permitted.
>
> "1/4 WELDING    LEVER FRONT DRW 14844-C  MAT  WMA1CM-WLFRONT"
> into
> "1/4 WELDING LEVER FRONT DRW 14844-C MAT WMA1CM-WLFRONT"
>
>
>
> I want to use the sub! method. Why does the below code not work? Is my
> pattern incorrect?
>
> descrip = "1/4 WELDING    LEVER FRONT DRW 14844-C  MAT  WMA1CM-WLFRONT"
> descrip.sub!(/\s+/,' ')
> puts descrip

sub! only affects the *first* match. You can substitute globally with 
gsub. Also you might as well only match 2 or more spaces:

descrip.gsub!(/\s\s+/,' ')

[toc] | [prev] | [next] | [standalone]

#3472

[Note:  parts of this message were removed to make it a legal post.]

On Mon, Apr 25, 2011 at 1:51 PM, Joel VanderWerf
<joelvanderwerf@gmail.com>wrote:

> On 04/25/2011 11:44 AM, Michelle Pace wrote:
>
>> Hello, I need to make the first string below into the second string.
>> That is, only single white spaces are permitted.
>>
>> "1/4 WELDING    LEVER FRONT DRW 14844-C  MAT  WMA1CM-WLFRONT"
>> into
>> "1/4 WELDING LEVER FRONT DRW 14844-C MAT WMA1CM-WLFRONT"
>>
>>
>>
>> I want to use the sub! method. Why does the below code not work? Is my
>> pattern incorrect?
>>
>> descrip = "1/4 WELDING    LEVER FRONT DRW 14844-C  MAT  WMA1CM-WLFRONT"
>> descrip.sub!(/\s+/,' ')
>> puts descrip
>>
>
> sub! only affects the *first* match. You can substitute globally with gsub.
> Also you might as well only match 2 or more spaces:
>
> descrip.gsub!(/\s\s+/,' ')
>
>

I think the original regex is better, because leads to more consistent
results:

"hello\tworld    !".gsub(/\s\s+/,' ') # => "hello\tworld !"
"hello\tworld    !".gsub(/\s+/,' ')   # => "hello world !"

[toc] | [prev] | [next] | [standalone]

#3474

On 04/25/2011 12:02 PM, Josh Cheek wrote:
> On Mon, Apr 25, 2011 at 1:51 PM, Joel VanderWerf
> <joelvanderwerf@gmail.com>wrote:
>
>> On 04/25/2011 11:44 AM, Michelle Pace wrote:
>>
>>> Hello, I need to make the first string below into the second string.
>>> That is, only single white spaces are permitted.
>>>
>>> "1/4 WELDING    LEVER FRONT DRW 14844-C  MAT  WMA1CM-WLFRONT"
>>> into
>>> "1/4 WELDING LEVER FRONT DRW 14844-C MAT WMA1CM-WLFRONT"
>>>
>>>
>>>
>>> I want to use the sub! method. Why does the below code not work? Is my
>>> pattern incorrect?
>>>
>>> descrip = "1/4 WELDING    LEVER FRONT DRW 14844-C  MAT  WMA1CM-WLFRONT"
>>> descrip.sub!(/\s+/,' ')
>>> puts descrip
>>>
>>
>> sub! only affects the *first* match. You can substitute globally with gsub.
>> Also you might as well only match 2 or more spaces:
>>
>> descrip.gsub!(/\s\s+/,' ')
>>
>>
>
> I think the original regex is better, because leads to more consistent
> results:
>
> "hello\tworld    !".gsub(/\s\s+/,' ') # =>  "hello\tworld !"
> "hello\tworld    !".gsub(/\s+/,' ')   # =>  "hello world !"
>

Good point, but it depends on what you're trying to be consistent with. 
Maybe the goal is to squeeze space, but preserve tab layout for readability.

[toc] | [prev] | [next] | [standalone]

#3476

[Note:  parts of this message were removed to make it a legal post.]

There is also the build-in method squeeze!, which does exacly this

str.squeeze!(" ")

[toc] | [prev] | [next] | [standalone]

#3513

Joel VanderWerf wrote in post #994935:
> On 04/25/2011 11:44 AM, Michelle Pace wrote:
>> pattern incorrect?
>>
>> descrip = "1/4 WELDING    LEVER FRONT DRW 14844-C  MAT  WMA1CM-WLFRONT"
>> descrip.sub!(/\s+/,' ')
>> puts descrip
>
> sub! only affects the *first* match. You can substitute globally with
> gsub. Also you might as well only match 2 or more spaces:
>
> descrip.gsub!(/\s\s+/,' ')

Those are not equivalent, because \s matches more than just ASCII 0x20.

d1 = "foo\tbar\tbaz"
d1.gsub(/\s+/,' ')    # "foo bar baz"
d1.gsub(/\s\s+/,' ')  # "foo\tbar\tbaz"

-- 
Posted via http://www.ruby-forum.com/.

[toc] | [prev] | [next] | [standalone]

#3519

On 04/26/2011 05:03 AM, Brian Candler wrote:
> Joel VanderWerf wrote in post #994935:
>> On 04/25/2011 11:44 AM, Michelle Pace wrote:
>>> pattern incorrect?
>>>
>>> descrip = "1/4 WELDING    LEVER FRONT DRW 14844-C  MAT  WMA1CM-WLFRONT"
>>> descrip.sub!(/\s+/,' ')
>>> puts descrip
>>
>> sub! only affects the *first* match. You can substitute globally with
>> gsub. Also you might as well only match 2 or more spaces:
>>
>> descrip.gsub!(/\s\s+/,' ')
>
> Those are not equivalent, because \s matches more than just ASCII 0x20.
>
> d1 = "foo\tbar\tbaz"
> d1.gsub(/\s+/,' ')    # "foo bar baz"
> d1.gsub(/\s\s+/,' ')  # "foo\tbar\tbaz"

[toc] | [prev] | [next] | [standalone]

#3521

On 04/26/2011 05:03 AM, Brian Candler wrote:
> Joel VanderWerf wrote in post #994935:
>> On 04/25/2011 11:44 AM, Michelle Pace wrote:
>>> pattern incorrect?
>>>
>>> descrip = "1/4 WELDING    LEVER FRONT DRW 14844-C  MAT  WMA1CM-WLFRONT"
>>> descrip.sub!(/\s+/,' ')
>>> puts descrip
>>
>> sub! only affects the *first* match. You can substitute globally with
>> gsub. Also you might as well only match 2 or more spaces:
>>
>> descrip.gsub!(/\s\s+/,' ')
>
> Those are not equivalent, because \s matches more than just ASCII 0x20.
>
> d1 = "foo\tbar\tbaz"
> d1.gsub(/\s+/,' ')    # "foo bar baz"
> d1.gsub(/\s\s+/,' ')  # "foo\tbar\tbaz"

You're right. What I said in another post about preserving tabs isn't 
what the original sub! call was doing anyway.

(sorry for the empty reply previously)

[toc] | [prev] | [next] | [standalone]

#3471

[Note:  parts of this message were removed to make it a legal post.]

Good Morning Michelle,

On Mon, Apr 25, 2011 at 11:44 AM, Michelle Pace
<michelle@michellepace.com>wrote:

> Hello, I need to make the first string below into the second string.
> That is, only single white spaces are permitted.
>
> "1/4 WELDING    LEVER FRONT DRW 14844-C  MAT  WMA1CM-WLFRONT"
> into
> "1/4 WELDING LEVER FRONT DRW 14844-C MAT WMA1CM-WLFRONT"
>
>
>
> I want to use the sub! method. Why does the below code not work? Is my
> pattern incorrect?
>
> descrip = "1/4 WELDING    LEVER FRONT DRW 14844-C  MAT  WMA1CM-WLFRONT"
> descrip.sub!(/\s+/,' ')
> puts descrip
>

Sub only replaces the first instance of the pattern. You require gsub! to
accomplish your task.

You noticed no difference with your sub! call because the first instance of
your pattern is the single space between 1/4 and WELDING so in essence sub!
did nothing to your string because it replaced a single space with a single
space.

John

[toc] | [prev] | [next] | [standalone]

#3509

Try gsub for multiple characters - Try code below: 
 
descrip = "1/4    WELDING                  LEVER FRONT DRW 14844-C MAT WMA1CM-WLFRONT"
puts descrip.gsub!(/\s+/,' ') 		 	   		  

[toc] | [prev] | [standalone]

Back to top | Article view | comp.lang.ruby

csiph-web