regexp that ignore case or check the case based on a variable

[Pierre]

Hello,

I would like to write a regexp that can be either case sensitive or that can
ignore the case based on a variable (value would be either 'i' or '').
For instance in the below code the variable is $case.
I can't make that piece of code working fine. Anyone can help please ?

my $str = "Hello World!";
my $pattern "hello";
my $case = "i";

if ($str =~ s/${pattern}/${case}) {
print "match!\n";
}


Thank you,
Pierre.

[cyber1]

Pierre-

You seem to have some other language mixed in here.
I'm not clear on what it is you want.

But try these:

my $str = "Hello World!";
my $pattern = "hello";

if ($str !~ m/$pattern/g){
print "no match1!\n";
}

##ignore case
if (lc($str) =~ m/$pattern/g){
print "match2!\n";
}

##use case option
if ($str =~ m/$pattern/gi){
print "match3!\n";
}

More on Perl Regexp:

http://www.pti.co.il/talks/Fundamentals/x936.html

-Bill

[Lars Kellogg-Stedman]

Re: regexp that ignore case or check the case based on a variable

> I would like to write a regexp that can be either case sensitive or that can[color=blue]
> ignore the case based on a variable (value would be either 'i' or '').
> For instance in the below code the variable is $case.
> I can't make that piece of code working fine. Anyone can help please ?
>
> my $str = "Hello World!";
> my $pattern "hello";
> my $case = "i";
>
> if ($str =~ s/${pattern}/${case}) {
> print "match!\n";
> }[/color]

The above code doesn't actually run, but I'm assuming that was just typos
when you posted it. It helps to put the code in a file and test it first.

As for solving your regex question, you might want to take a look at:

perldoc perlre

Read the section entitled "Extended Patterns". You can set regex flags
(such as "i" for "ignore case") in the pattern itself. For example:

my $str = "Hello World!";
my $case = "i";
my $pattern = "(?$case)hello" ;

if ($str =~ /${pattern}/) {
print "match!\n";
}

-- Lars

--
larsks@hotmail. com