Regular Expression help!

[shilpa]

Hello,

I am trying to parse string buffer by using Regular Expression.
Suppose my string buffer is:

-------------------------------------------
Hi , How are you?

Hello: abc

hurrey : [ this is test msg
Pls reply to this mail
Hello: xyz
Test1
]

-------------------------------------------

I want to search string: "Hello: anystring till end of line" which is
not included in [].
So In above example my Regular expression should only find

first "Hello: abc".

Is it possible by using Regular expression?

 

[Roedy Green]

Is it possible by using Regular expression?

see http://mindprod.com/jgloss/regex.html

 

[Roedy Green]

Is it possible by using Regular expression?

Yes. To find out how, see http://mindprod.com/jgloss/regex.html

You need to learn regex as a whole.

 

[Oliver Wong]

Hello,

I am trying to parse string buffer by using Regular Expression.
Suppose my string buffer is:

-------------------------------------------
Hi , How are you?

Hello: abc

hurrey : [ this is test msg
Pls reply to this mail
Hello: xyz
Test1
]

-------------------------------------------

I want to search string: "Hello: anystring till end of line" which is
not included in [].
So In above example my Regular expression should only find

first "Hello: abc".

Is it possible by using Regular expression?

I don't think this is possible, particularly if you allow nesting of
brackets. Consider:

[[[[]]]
Hello: How are you?
[[[]]]]

This requires bracket-balancing, which requires at least the power of a
context-free grammar, so no, regular expressions are not powerful enough to
accept this language.

- Oliver