Interpolation problem

[Pal Hulden]

Say I have this case:

----
#!/usr/bin/perl -w
$a = "(I leave now";
$_ = "Goodbye (I leave now)";
s/$a//;
print "$_\n";
----

I would like to expect

Goodbye )

as an answer. This does obviously not work (get unmatching parenthesis
error) due to more interpolation that I wanted. I have and have read
Wall/Christiansen/Schwarz' book 'Programming Perl' but I cannot find
the solution to the problem in there.

What is the correct syntax?

Please help.

Sincerely
Pål Huldén
Gothenburg
Sweden

 

[Kien Ha]

Say I have this case:

----
#!/usr/bin/perl -w
$a = "(I leave now";
$_ = "Goodbye (I leave now)";
s/$a//;
print "$_\n";
----

I would like to expect

Goodbye )

as an answer. This does obviously not work (get unmatching parenthesis
error) due to more interpolation that I wanted. I have and have read
Wall/Christiansen/Schwarz' book 'Programming Perl' but I cannot find
the solution to the problem in there.

What is the correct syntax?

perldoc -f quotemeta

$a = quotemeta $a;
s/$a//;

or
s/\Q$a//;

 

[Gunnar Hjalmarsson]

Say I have this case:

----
#!/usr/bin/perl -w
$a = "(I leave now";
$_ = "Goodbye (I leave now)";
s/$a//;
print "$_\n";
----

I would like to expect

Goodbye )

as an answer. This does obviously not work (get unmatching
parenthesis error) due to more interpolation that I wanted. I have
and have read Wall/Christiansen/Schwarz' book 'Programming Perl'
but I cannot find the solution to the problem in there

What is the correct syntax?

s/\Q$a//;
------^^

Check out perldoc perlre.

Gothenburg Sweden

Really? Me too.