string =~ string expressions

[Mark James]

Hi,

According to both http://www.ruby-doc.org/core/classes/String.html#M001334
and http://www.ruby-doc.org/docs/ProgrammingRuby/html/ref_c_string.html#String._eq_sd
I should be able to type:
"cat o' 9 tails" =~ "\\d"
and get a match result.

But in Ruby 1.8.2 I'm getting the error:

`=~': type mismatch: String given (TypeError)

[Robert Klemme]

I believe this has changed at some place in time (between 1.6 and 1.8 as
far as I can recall). It seems the documentation is not up to date.

I'd prefer to use /\d/ =~ "cat o' 9 tails", "cat o' 9 tails" =~ /\d/ or
"cat o' 9 tails" =~ Regexp.new "\\d" - assuming "\\d" is some kind of user
entered string.

Kind regards

robert

[gregarican]

Make James wrote:

> Hi,
>
>
> According to both http://www.ruby-doc.org/core/classes/String.html#M001334

> and http://www.ruby-doc.org/docs/ProgrammingRuby/html/ref_c_string.html#S...

> I should be able to type:
> "cat o' 9 tails" =~ "\\d"
> and get a match result.

> But in Ruby 1.8.2 I'm getting the error:

> `=~': type mismatch: String given (TypeError)

Try "cat o' 9 tails" =~ /\d/

[Mark James]

Robert Klemme wrote:

> I'd prefer to use /\d/ =~ "cat o' 9 tails", "cat o' 9 tails" =~ /\d/ or
> "cat o' 9 tails" =~ Regexp.new "\\d" - assuming "\\d" is some kind of user
> entered string.

Thanks Robert, I am trying to match against a r.e. held in a string variable.
It works as: "cat o' 9 tails" =~ (Regexp.new "\\d")

[Chris Game]

gregarican wrote:

"In previous versions of Ruby, both [operands] could be strings, in
which case the second operand was converted into a regular
expression behind the scenes" - p.69 of the cited book above.

--
Chris Game

"Everything that can be said can be said clearly."
-- Ludwig Wittgenstein

[Mark James]

Chris Game wrote:

> "In previous versions of Ruby, both [operands] could be strings, in
> which case the second operand was converted into a regular
> expression behind the scenes" - p.69 of the cited book above.

OK, thanks. This must be in the Second Edition of the book
<http://www.ruby-doc.org/docs/ProgrammingRuby/>, not
the First Edition on the Web.

[Chris Game]

Mark James wrote:

Right. The 2nd Ed. still needs better editing though - hopefully a
3rd Ed. will come out eventually.

--
Chris Game

Calm down -- it's only ones and zeroes