From f18e1cc1d8a49f69404d6d37c1bf0d675ba6022c Mon Sep 17 00:00:00 2001
From: Jörg Sommrey <28217714+jo-37@users.noreply.github.com>
Date: Tue, 5 Mar 2024 23:08:46 +0100
Subject: Solution to task 2

---
 challenge-259/jo-37/perl/ch-2.pl | 130 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 130 insertions(+)
 create mode 100755 challenge-259/jo-37/perl/ch-2.pl

diff --git a/challenge-259/jo-37/perl/ch-2.pl b/challenge-259/jo-37/perl/ch-2.pl
new file mode 100755
index 0000000000..49c825020c
--- /dev/null
+++ b/challenge-259/jo-37/perl/ch-2.pl
@@ -0,0 +1,130 @@
+#!/usr/bin/perl -s
+
+use v5.24;
+use Test2::V0;
+use Regexp::Common qw(number delimited);
+use Clone 'clone';
+use Data::Dump 'dd';
+
+our ($tests, $examples);
+
+run_tests() if $tests || $examples;	# does not return
+
+die <<EOS unless @ARGV;
+usage: $0 [-examples] [-tests] [STR]
+
+-examples
+    run the examples from the challenge
+ 
+-tests
+    run some tests
+
+STR
+    string to be parsed
+
+EOS
+
+
+### Input and Output
+
+dd line_parser(shift);
+
+
+### Implementation
+
+sub unescape {
+    shift =~ s{\\(.)}{$1}gr;
+}
+
+sub line_parser {
+    our %tmp;
+    our $val;
+    my $parsed;
+
+    shift =~ m{
+        (?{ local %tmp })
+        \{% \s*+
+        (?<NAME>\w++)
+        (?{ $tmp{name} = $+{NAME}; })
+        (?:
+            \s++
+            (?<KEY>\w++)=
+            (?{ local $val; })
+            (?:
+                (??{qr{$RE{num}{dec}{-keep}
+                        (?{ $val = 0 + $1; })
+                    }x
+                })
+                |
+                (??{qr{$RE{delimited}{-delim => q{'"}}{-esc => '\\'}{-keep}
+                        (?{ $val = unescape($3); })
+                    }x
+                })
+            )
+            (?{ $tmp{fields}{$+{KEY}} = $val; })
+        )*+
+        \s*+ %\}
+        (?:
+            \n
+            (?<LINES>.*?)
+            \n
+            (?{ $tmp{text} = $+{LINES}; })
+            \{% \s*+
+            end\g{NAME}
+            \s*+ %\}
+        )?
+        (?{ $parsed = clone \%tmp; })
+    }xs;
+
+    $parsed;
+}
+
+
+### Examples and tests
+
+sub run_tests {
+    SKIP: {
+        skip "examples" unless $examples;
+
+        is line_parser(
+            '{%  id   field1="value1"    field2="value2"  field3=42 %}'
+        ), {name => 'id',
+            fields => {field1 => 'value1', field2 => 'value2', field3 => 42}},
+            'example 1';
+        is line_parser('{%  youtube title="Title \"quoted\" done" %}'),
+            {name => 'youtube', fields => { title => q{Title "quoted" done}}},
+            'example 2';
+        is line_parser(
+            '{%  youtube title="Title with escaped backslash \\\\" %}'
+        ), {name => 'youtube',
+            fields => {title => q{Title with escaped backslash \\}}},
+            'example 3';
+        is line_parser(<<'EOD'),
+{% id  field1="value1" %}
+LINE1
+LINE2
+{% endid %}
+EOD
+            {name => 'id', fields => {field1 => 'value1'},
+                text => "LINE1\nLINE2"}, 'example 4';
+    }
+
+    SKIP: {
+        skip "tests" unless $tests;
+
+        is line_parser('{% no_fields %}'), {name => 'no_fields'}, 'no fields';
+        is line_parser('{% no_end'), F(), 'incomplete';
+        is line_parser('{% inval f1=abc %}'), F(), 'unquoted string';
+        like line_parser('{% numstr f1="042" f2=043 f3=44.0e0 f4="45.0" f5="aaa" %}'),
+            hash { field name => 'numstr'; field fields => hash {
+                    field f1 => qr/^042$/; field f2 => qr/^43$/;
+                    field f3 => qr/^44$/; field f4 => qr/^45\.0$/;
+                    field f5 => qr/^aaa$/;}},
+            'numbers';
+        is line_parser(q{{% single_quote f1='one' %}}),
+            {name => 'single_quote', fields => {f1 => 'one'}}, 'single quote';
+	}
+
+    done_testing;
+    exit;
+}
-- 
cgit