Problem with String.gsub and \' as a replacement string

Ruby
1

Hi,

I want to replace all occurences of a certain character in a string
with a backslash followed by a single quote. Sounds like a trivial
task, but this is what I get:

“this is a test”.gsub( “a”, “\’” ) -> “this is test test”

What I want is “this is ’ test”.

Neither does this work:
“this is a test”.gsub( “a”, ‘’ + “’” )

No matter what I am doing, as soon as a backslash is followed by a
single quote in the replacement string, I am getting weird results.

Thanks for your help!

Andreas

2

ridcully wrote:

Neither does this work:
“this is a test”.gsub( “a”, ‘’ + “’” )

No matter what I am doing, as soon as a backslash is followed by a
single quote in the replacement string, I am getting weird results.
Backslashes are confusing. Try this:

puts “this is a test”.gsub( “a”, “\\’” )

3

On 17 Nov., 12:22, Alex Y. [email protected] wrote:

Backslashes are confusing. Try this:

puts “this is a test”.gsub( “a”, “\\'” )

–
Alex

Thank you, you saved my day!

This really is confusing, because “\'” gives me the correct result if
I don’t use it with gsub:

puts “\'” → '

Am I missing something here?

Andreas

4

On Nov 17, 2007 7:20 PM, ridcully [email protected] wrote:

“this is a test”.gsub( “a”, “\'” ) → “this is test test”

many ways, eg

~> “this is a test”.gsub(“i”,Regexp.escape(“\'”))
=> “th\'s \'s a test”

~> “this is a test”.gsub(“i”){“\'”}
=> “th\'s \'s a test”

the block form seems clean though.

kind regards -botp

5

ridcully wrote:

Am I missing something here?
“\’” translates to a literal backslash followed by ‘. This is what gsub
gets.
gsub then sees ’ and replaces it with $’ the same way it would replace
\1
with $1. To tell it not to do that it has to get \’, so it knows it’s
not
supposed to treat ’ as special. In order to archieve that you have to
write “\\’”. Hope that cleared things up for you.