How can I do this with regex?

[Ahmet Kilic]

I want to grep Delphi "class name" and "reference classes" in a delphi
class file.
How can I do that with regex?

example delphi class like this;

http://exampledelphi.com/?p=62

any idea?

 

[Marc Heiler]

I want to grep Delphi "class name" and "reference classes" in a delphi
class file.
How can I do that with regex?

example delphi class like this;

http://exampledelphi.com/?p=62

any idea?

What do you want to do? Grep through a text for a specific string?

"string".grep //

I dont think that many will understand delphi here (isnt delphi
graphical btw? not sure how this compares to ruby...) so it is best to
try to formulate the question more ruby specific (or neutral so that
others have an easier time to understand it)

 

[Michael Brooks]

Hello Ahmet:

I'm not a Ruby guru or anything, I still do most of my coding in Delphi (I
love Ruby but it's too slow). However, here are a few hints to help you do
what I think your wanting to do (note: each assumes you've filled
current_line with a line of text from your Delphi code):

1) Returns true if current_line contains something like " TMyClass = class
(TObject)" :
-> current_line.match(/=\sclass\b/i)

2) Returns the class name (e.g. TMyClass) from current_line found with the
regex from #1:
-> current_line.match(/^\s*T(\w*)/)

3) Returns true if the current_line variable starts with and only contains
the word "implementation" which will be important for you to know when your
about to enter the implementation section:
-> current_line.match(/^\s*implementation\s*$/i)

4) You'll need to keep track of the class names you've captured and use a
regex in the implementation section to find when you've found a usage of a
class. I'll leave that to you to figure out. However, testing for a word
(i.e. the class name) on it's own using regex word boundaries with something
like this should help:
-> current_line.match(/\bTMyClass\b/i)

5) You can use variables (e.g. each class name you're searching for) within
a regex by wrapping it in #{} like this:
-> current_line.match(/#{myvariable}/)

6) This Ruby feature seems to be very usefull for code parsing, it tells you
that you're currently between lines that contains "begin" and "end".
-> current_line.match(/begin/i) ... current_line.match(/end/i)

7) Google is your friend; here are a few links (including an online regex
evaluator to play with) I found usefull...
http://rubular.com/
http://www.rubyxp.com/
http://www.rubyist.net/~slagell/ruby/regexp.html
http://codelikezell.com/how-to-use-ruby-variables-in-regular-expressions/
http://www.regular-expressions.info/ruby.html

Good Luck,

Michael

 

[Michael Brooks]

Hello Ahmet:

I'm not a Ruby guru or anything, I still do most of my coding in Delphi (I
love Ruby but it's too slow). However, here are a few hints to help you do
what I think your wanting to do (note: each assumes you've filled
current_line with a line of text from your Delphi code):

1) Returns true if current_line contains something like " TMyClass = class
(TObject)" :
-> current_line.match(/=\sclass\b/i)

2) Returns the class name (e.g. TMyClass) from current_line found with the
regex from #1:
-> current_line.match(/^\s*T(\w*)/)

3) Returns true if the current_line variable starts with and only contains
the word "implementation" which will be important for you to know when your
about to enter the implementation section:
-> current_line.match(/^\s*implementation\s*$/i)

4) You'll need to keep track of the class names you've captured and use a
regex in the implementation section to find when you've found a usage of a
class. I'll leave that to you to figure out. However, testing for a word
(i.e. the class name) on it's own using regex word boundaries with something
like this should help:
-> current_line.match(/\bTMyClass\b/i)

5) You can use variables (e.g. each class name you're searching for) within
a regex by wrapping it in #{} like this:
-> current_line.match(/#{myvariable}/)

6) This Ruby feature seems to be very usefull for code parsing, it tells you
that you're currently between lines that contains "begin" and "end".
-> current_line.match(/begin/i) ... current_line.match(/end/i)

7) Google is your friend; here are a few links (including an online regex
evaluator to play with) I found usefull...
http://rubular.com/
http://www.rubyxp.com/
http://www.rubyist.net/~slagell/ruby/regexp.html
http://codelikezell.com/how-to-use-ruby-variables-in-regular-expressions/
http://www.regular-expressions.info/ruby.html

Good Luck,

Michael

 

[Ahmet Kilic]

Michael, Thank you very very much.
It is very usefull.

 

[David Masover]

I'm not a Ruby guru or anything, I still do most of my coding in Delphi (I
love Ruby but it's too slow).

I'm curious -- do you have any numbers to back this up? Or any real
applications you tried in Ruby, and found it was too slow?

Or is it that Delphi is somehow faster to develop in?

I'm not saying you're wrong, but I do most of my coding in Ruby, because I
rarely find places it's too slow. I'm always curious what those edge cases are
that need another tool.

 

[Michael Brooks]

I'm curious -- do you have any numbers to back this up? Or any real
applications you tried in Ruby, and found it was too slow?

Or is it that Delphi is somehow faster to develop in?

I'm not saying you're wrong, but I do most of my coding in Ruby, because I
rarely find places it's too slow. I'm always curious what those edge cases
are
that need another tool.

Hello David:

Regarding code development speed: For complex web applications (I use
Delphi's built-in IntraWeb framework) and many Windows GUI applications I
find Delphi much faster to work with. The language and DB data providers
are archaic by Ruby / Python standards but the integration between the IDE,
language, built in components and the host windowing environment saves so
much time for most of the projects I've worked on (e.g. database
applications, graphics engines, data visualization, data generation /
simulation, general utilities / home projects). I've tried Ruby Rails
before Delphi IntraWeb, it was easy to build simple stuff but as the visual
and functional complexity went up it was just easier to use Delphi IntraWeb.
I didn't know IntraWeb at the time but it's WYSIWYG design environment for
the web pages which was tightly integrated with the Delphi code was so much
faster to develop with... not like the "code generator / run it and see what
it looks like" feel I got from Rails.

Regarding execution speed: I love the true OOP and metaprogramming of Ruby
but it's so slow executing compared to a compiled language like Java, C++ or
Delphi. A while ago I wrote a simple test to calculate prime numbers with
Delphi, Python and Ruby (using the same brute force approach in each) and
found:

Delphi (v6.0) = 1.52s
Delphi (v2009) = 3.41s = 2.24 times slower than Delphi v6
Python (v2.8) = 54.25s = 35.69 times slower than Delphi v6
Ruby (v1.8.6) = 121.82s = 80.14 times slower than Delphi v6
Ruby (v1.9.1) = 53.70s = 35.33 times slower than Delphi v6

using a Pentium 4, 3.0 Ghz, 1GB Memory, Windows XP SP2. I did the same test
on SUSE Linux 10.2 and found Ruby to be about 30% faster than the results on
Windows (note: Python was 20% slower on SUSE Linux so compilers and memory
management appear to make a big difference).

That's not the only program I've written in both Delphi and Ruby. I ported
a Ruby XMLTV viewer (which deals with a little over a gigabyte of data) to
Delphi and the Delphi program ran 2.5 times faster (i.e. 63 seconds vs 160
seconds). The Delphi program was at a disadvantage because the Delphi
component I used applied an in-memory XML DOM approach vs the Ruby
component's XML SAX approach (i.e. more memory overhead and validation for
the Delphi program).

The OpenGL graphics engine I wrote in Ruby was very fast in the beginning
(2100 FPS) for a simple 3D scenes because most of the work was being done on
the GPU but as the engine grew to include reflection, shadows, AI (all of
which require more passes per frame on the Ruby side) then it really slowed
down (i.e. 60 FPS and dropping). I'm still working on this project and hope
to find better ways to use Ruby but found that Delphi didn't slow down as
quickly in similar situations.

I also starting writing a source code translator (which is why I had some
advice for this thread) which relied heavily on Ruby gsubs. It's a lot
faster than I expected (maybe %80 of the speed of an equivalent Delphi
program) but that's likely because the gsubs are doing most of the work.

Ruby really gets killed by looping through stuff. For my graphics engines
that means multi-passes on 3d objects for the diffuse, reflection and shadow
passes. For XML parsing that means going through all the records in the XML
file and parsing the tags/containers. For the pirme number calculator that
was simple looping. Ruby does great if you can let the behind the scenes
optimized functions (or external C/C++ libraries) do most of the work.

I"m not saying I used the best designs for either my Ruby or Delphi programs
but for all the tricks and neat stuff I can do in Ruby there are limits to
the time I'm willing to invest in Ruby (i.e to write external routines or
redesign things to use Ruby smarter) to get the speed I need.

I've seen the "Ruby / Python / Lua / etc is fast enough for me" discussion
on various forums several times and it usually depends on the kind of thing
you're trying to use the language for. In my case I'm using Ruby for some
of the worst case senarios that you can throw at an interpretive / VM
language.

However, to Ruby's credit because of it's dynamic nature and true OOP I can
do some things in Ruby for my game engine that I've always wished I could do
in Delphi so I haven't given up hope on it yet. The speed is the only real
issue.

Did I answer you question?

Michael

p.s. Please forgive any poor grammer, etc... it's a long response and I
don't want to re-read it to many times.