To understand grammars better, I figured I would convert Config::Tiny to Perl
6. I've started with the following:
grammar Config::Tiny::Grammar {
token TOP {
<root_section>?
<section>+
}
token root_section {
<property>+
}
token section {
^^ '[' \s* $<name>=<-[\n\]]>* \s* ']' \n
<property>*
}
token property {
^^ \s* $<name>=<-[=]>* \s* '=' \s* $<value>=[\N*] \n
}
}
my $text = Q{
[foo]
};
my $config = Config::Tiny::Grammar.parse($text);
#say $config ?? 'yes' || 'no';
say $config.perl;
Currently this matches, but if I add a \s* before the final \n in the section
token, it fails to match. I don't know why this is and I'm unsure of how to
debug Perl 6 regexes.
Also, if I uncomment that 'say $config ??' line, I get the following strange
error:
ResizablePMCArray: Can't pop from an empty array!
in Main (file <unknown>, line <unknown>)
And adding any "property" lines like "bar=baz" causes the grammar to fail to
match, or switching "<section>+" to "<section>*" in the TOP token causes the
grammar to fail to match. In short, just about anything I touch seems to break
the grammar :)
Any suggestions welcome.
Cheers,
Ovid--
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