How do I best do balanced quoting with Perl's Regexp::Grammars?
- by Evan Carroll
Using Damian Conway's Regexp::Grammars, I'm trying to match different balanced quoting ('foo', "foo", but not 'foo") mechanisms -- such as parens, quotes, double quotes, and double dollars. This is the code I'm currently using.
<token: pair> \'<literal>\'|\"<literal>\"|\$\$<literal>\$\$
<token: literal> [\S]+
This generally works fine and allows me to say something like:
<rule: quote> QUOTE <.as>? <pair>
My question is how do I reform the output, to exclude the needles notation for the pair token?
{
'' => 'QUOTE AS \',\'',
'quote' => {
'' => 'QUOTE AS \',\'',
'pair' => {
'literal' => ',',
'' => '\',\''
}
}
},
Here, there is obviously no desire to have pair in between, quote, and the literal value of it. Is there a better way to match 'foo', "foo", and $$foo$$, and maybe sometimes ( foo ) without each time creating a needless pair token? Can I preprocess-out that token or fold it into the above? Or, write a better construct entirely that eliminates the need for it?