Regular expressions when searching for string containing brackets or parans ..

[Joe Halbrook]

I am trying to search a string that may contain brackets or parenthesis.
Could someone suggest a way to do this such that the seacrh will not
fail, when the string search does contain the special character, i.e.

if ($searchstring =~ /$_/i) {

when $searchstring and $_ may contain a string with a [, ], (, or ) character?

Much thanks, in advance.

Joe Halbrook

 

[Tedd Hansen]

From the manual;
if ($searchstring =~ /\Q$_\E/i) {

it quotes the string correctly before processing the regex

- Tedd

 

[Tad McClellan]

[ please do not top-post. Text rearranged. ]




That's the "Quote and Quote-like Operators" section of the perlop manual.

Will this work even if $searchstring contains an "reserved"
character, or should I:

$newsearchstring =~ /\Q$searchstring\E/i)

Please use copy/paste with *real* code.

Was the parenthesis supposed to be a semicolon?

if ($newsearchstring =~ /\Q$_\E/i) {

Backslash escapes, such as \Q and \n, work in "double quotish" strings.

The match operator is "double quotish", but you can also use them in
actual double-quoted strings.

So, use one in a double-quoted string and then print the string
to see what it did:

my $searchstring = 'open paren(';
my $str = "\Q$searchstring";
print "$str\n";


See also the named function that does the same thing:

perldoc -f quotemeta