Regex: multiline

Ruby
1

Hello,

I am trying regex samples on this page
Learning to Use Regular Expressions.
My problem is, how can I grep multiline with regex?

This is my example;
…
*****************************************************************************)
function TfrmExecMain.SetPrivilege(PrivilegeName: String;
Enable: Boolean): Boolean;
var
tpPrev,
tp : TTokenPrivileges;
token : THandle;
dwRetLen : DWord;
begin
…
I want to print some parts of this.

for example;
if function=~/\b(^function)\s+(\w+)/
print this part===> : Boolean;
end
if line.match(/var/) and line.match(/begin/)
print this part ==> : TTokenPrivileges;
print this part ==> : THandle;
and print this ==> : DWord;
end

How can i do it?

2

thank you very much.

3

2009/9/10 7stud – [email protected]:

function TfrmExecMain.SetPrivilege(PrivilegeName: String;
for example;

ENDOFSTRING

md = str.match(/function.?):\s+(.?;)/m)
if md
 puts md[1]
end

–output:–
Boolean;

Note that you do not need the /m flag for this to match. This works
the same without it. The only difference that /m makes is whether
newlines are matched by .:

irb(main):001:0> s = “a\nb\n”
=> “a\nb\n”
irb(main):002:0> s[/./]
=> “a”
irb(main):003:0> s[/./m]
=> “a\nb\n”

It does not make any difference for \s:

irb(main):004:0> s[/\s+/]
=> “\n”
irb(main):005:0> s[/\s+/m]
=> “\n”

I’ll attach an extended example.

Kind regards

robert

4

Ahmet K. wrote:

Hello,

I am trying regex samples on this page
Learning to Use Regular Expressions.
My problem is, how can I grep multiline with regex?

This is my example;
…
*****************************************************************************)
function TfrmExecMain.SetPrivilege(PrivilegeName: String;
Enable: Boolean): Boolean;
var
tpPrev,
tp : TTokenPrivileges;
token : THandle;
dwRetLen : DWord;
begin
…
I want to print some parts of this.

for example;
if function=~/\b(^function)\s+(\w+)/
print this part===> : Boolean;
end
if line.match(/var/) and line.match(/begin/)
print this part ==> : TTokenPrivileges;
print this part ==> : THandle;
and print this ==> : DWord;
end

How can i do it?

str = <<ENDOFSTRING
function TfrmExecMain.SetPrivilege(PrivilegeName: String;
Enable: Boolean): Boolean;
var
tpPrev,
tp : TTokenPrivileges;
token : THandle;
dwRetLen : DWord;
begin
ENDOFSTRING

md = str.match(/function.?):\s+(.?;)/m)
if md
puts md[1]
end

–output:–
Boolean;

results = []
should_parse = false

str.each_line do |line|
line = line.chomp

if line == “var”
should_parse = true
elsif line == “begin”
should_parse = false
end

if should_parse
line.scan(/\w+;$/) do |match|
results << match
end
end
end

p results

–output:–
[“TTokenPrivileges;”, “THandle;”, “DWord;”]

5

2009/9/10 Ahmet K. [email protected]:

end
irb(main):002:0> s[/.*/]

for example;
tpPrev,
tp : TTokenPrivileges;
token : THandle;
dwRetLen : DWord;
begin
…
how can I do it with your code?
should I write new regexp for each function?

No, you simply need to replace the outer match with a call to
String#scan.

Cheers

robert

6

Robert K. wrote:

2009/9/10 7stud – [email protected]:

function TfrmExecMain.SetPrivilege(PrivilegeName: String;
for example;

ENDOFSTRING

md = str.match(/function.?):\s+(.?;)/m)
if md
 puts md[1]
end

–output:–
Boolean;

Note that you do not need the /m flag for this to match. This works
the same without it.

Note that you are wrong:

str =<<ENDOFSTRING
function TfrmExecMain.SetPrivilege(PrivilegeName: String;
Enable: Boolean): Boolean;
var
tpPrev,
tp : TTokenPrivileges;
token : THandle;
dwRetLen : DWord;
begin
ENDOFSTRING

md = str.match(/function.?):\s+(.?;)/m)
p md
md = str.match(/function.?):\s+(.?;)/)
p md

–output:–
#MatchData:0x2529c
nil

7

Robert K. wrote:

2009/9/10 7stud – [email protected]:

function TfrmExecMain.SetPrivilege(PrivilegeName: String;
for example;

ENDOFSTRING

md = str.match(/function.?):\s+(.?;)/m)
if md
 puts md[1]
end

–output:–
Boolean;

Note that you do not need the /m flag for this to match. This works
the same without it. The only difference that /m makes is whether
newlines are matched by .:

irb(main):001:0> s = “a\nb\n”
=> “a\nb\n”
irb(main):002:0> s[/./]
=> “a”
irb(main):003:0> s[/./m]
=> “a\nb\n”

It does not make any difference for \s:

irb(main):004:0> s[/\s+/]
=> “\n”
irb(main):005:0> s[/\s+/m]
=> “\n”

I’ll attach an extended example.

Kind regards

robert

Thank you Robert,
Wooow! your code is seen perfect.
I want to ask one more question; my file contains many many functions,
vars and begins like this,
for example;
…
function TfrmExecMain.GetApiErrorMessage(ApiErrCode :DWORD) :String;
var
Buf: array[0…511] of Char;
MsgCnt :DWORD;
begin
…
function TfrmExecMain.SetPrivilege(PrivilegeName: String;
Enable: Boolean): Boolean;
var
tpPrev,
tp : TTokenPrivileges;
token : THandle;
dwRetLen : DWord;
begin
…
how can I do it with your code?
should I write new regexp for each function?

8

Robert K. wrote:

2009/9/10 Ahmet K. [email protected]:

end
irb(main):002:0> s[/.*/]

for example;
�tpPrev,
�tp � � � � : TTokenPrivileges;
�token � � �: THandle;
�dwRetLen � : DWord;
begin
…
how can I do it with your code?
should I write new regexp for each function?

No, you simply need to replace the outer match with a call to
String#scan.

Cheers

robert

If I write this part of code it is seen OK for me,

str.scan(/[^;]+;/) do |var|
if /\A([^:]+):([^:]+);\z/ =~ var
names = $1
type = $2.strip

  names.split(/,/).each do |name|
    printf "var: type: %-20s name: %-20s\n", type, name.strip
  end
else
  puts "error with var #{var.inspect}"
end

end

but

No, you simply need to replace the outer match with a call to
String#scan.
what is the “replace the outer match” meaning? please explain a bit
more.

7stud: I recognize it also. It is not working for me. I am using ruby
1.8.6 (2007-09-24 patchlevel 111) [i386-mswin32]

thanks.