Perl's correspondent string literal for Python's prefix r"text"?

Question

This thread is about Python's string literal r, while this is about Perl's one here. However, I am not sure if there exists any equivalent command in Perl for Python's prefix r.

How can you replace equivalently Python's prefix r in Perl's string literals?

Answer 1

The uninterpolated quote operator q{} will get you most of the way there. There are only a couple of subtle differences.

1. delimiters

   There are four delimiters used with Python raw string literals:

   • r"..." and r'...'
   • r"""...""" and r'''...'''

   The q... operator in Perl has a greater variety of delimiters

   • Paired delimiters q(...), q[...], q<...>, q{...}
   • Regular delimiters can be any other non-alphanumeric, 7-bit ASCII char: q"...", q/.../, q#...#, etc.

2. the backslash

   The backslash character \ is always interpreted as a literal backslash character in Python raw literal strings. It will also escape a character that would otherwise be interpreted as the closing delimiter of the string

   r'Can\'t believe it\'s not butter'   =>   Can\'t believe it\'s not butter
   

   The backslash character \ in a Perl q{...} expression is also a literal backslash with two exceptions:

   • The backslash precedes a delimiter character

     q<18 \> 17 \< 19>     =>   18 > 17 < 19
     q#We're \#1#          =>   We're #1
     

   • The backslash precedes another backslash character. In this case the sequence of two backslash characters is interpreted as a single backslash.

     q[single \ backslash]           =>  single \ backslash
     q[also a single \\ backslash]   =>  single \ backslash
     q[double \\\ backslash]         =>  double \\ backslash
     q[double \\\\ backslash]        =>  double \\ backslash
     

There is one way to create a truly "raw" string in Perl: A single-quoted here-doc.

my $string = <<'EOS';
'"\\foo
EOS 

This creates the string '"\\fooNEWLINE.

(So is it possible to create a single raw string literal in Python that contains both ''' and """?)