Regex: Get Class Name

[Ahmet Kilic]

This a C++ class name,
const std::string DRAPBase::CLASS_NAME = "DRAPBase";
I am writing like this
classname = text.scan(/::CLASS_NAME = (.*?)\s+";/)
but it is not true.
how can I get the class name with regex?

 

[Brian Candler]

This a C++ class name,
const std::string DRAPBase::CLASS_NAME = "DRAPBase";
I am writing like this
classname = text.scan(/::CLASS_NAME = (.*?)\s+";/)
but it is not true.

You're matching `::CLASS_NAME = ' followed by zero or more characters
followed by one or more space characters followed by ";

It's the "one or more space characters" which doesn't match. Maybe you
meant \S which means non-space character? e.g.

classname = text.scan /::CLASS_NAME = "(\S+?)";/

 

[Robert Klemme]

You're matching `::CLASS_NAME =3D ' followed by zero or more characters
followed by one or more space characters followed by ";

It's the "one or more space characters" which doesn't match. Maybe you
meant \S which means non-space character? e.g.

classname =3D text.scan /::CLASS_NAME =3D "(\S+?)";/

I'd probably do

/::CLASS_NAME\s*=3D\s*"([^"]+)"/

Note to OP: (.*?) is a particular awful construction especially with a
variable length match pattern afterwards. As long as there is at
least one space (.*?) will always match the empty string in this case:

irb(main):010:0> 5.times {|i| p /(.*?)\s+/ =3D~ (" " * i), $1, $&, '---'}
nil
nil
nil
"---"
0
""
" "
"---"
0
""
" "
"---"
0
""
" "
"---"
0
""
" "
"---"
=3D> 5
irb(main):011:0>

Kind regards

robert

--=20
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/

 

[Ryan Davis]

I'd probably do

/::CLASS_NAME\s*=\s*"([^"]+)"/

I'd generally agree with that, but as I told the OP in IRC, in this
case I think it is better to think outside the box:

name = src[/(\w+)::CLASS_NAME\s*=/, 1]

Since that is the real name, it makes more sense to me.

 

[Ahmet Kilic]

I'd probably do

/::CLASS_NAME\s*=\s*"([^"]+)"/

I'd generally agree with that, but as I told the OP in IRC, in this
case I think it is better to think outside the box:

name = src[/(\w+)::CLASS_NAME\s*=/, 1]

Since that is the real name, it makes more sense to me.

thank you very much.

 

[Robert Klemme]

I'd probably do

/::CLASS_NAME\s*=\s*"([^"]+)"/

I'd generally agree with that, but as I told the OP in IRC, in this case I
think it is better to think outside the box:

name = src[/(\w+)::CLASS_NAME\s*=/, 1]

Since that is the real name, it makes more sense to me.

Ah, that wasn't obvious from the original posting.

Btw, this looks suspiciously like someone is trying to model dynamic
language features in C++. How simple that would be in Ruby

name = any_class.name



Kind regards

robert