Replace any multiple whitespaces with single white space

Ruby
1

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

2

On 04/25/2011 11:44 AM, Michelle P. 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+/,’ ')

3

Good Morning Michelle,

On Mon, Apr 25, 2011 at 11:44 AM, Michelle P.
[email protected]wrote:

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

4

On 04/25/2011 12:02 PM, Josh C. wrote:

“1/4 WELDING LEVER FRONT DRW 14844-C MAT WMA1CM-WLFRONT”

“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.

5

On Mon, Apr 25, 2011 at 1:51 PM, Joel VanderWerf
[email protected]wrote:

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 !”

6

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

str.squeeze!(" ")

7

Try gsub for multiple characters - Try code below:

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

8

Joel VanderWerf wrote in post #994935:

On 04/25/2011 11:44 AM, Michelle P. 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”

9

On 04/26/2011 05:03 AM, Brian C. wrote:

10

On 04/26/2011 05:03 AM, Brian C. wrote:

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)