css 0.0.22

// This file is part of css. It is subject to the license terms in the COPYRIGHT file found in the top-level directory of this distribution and at https://raw.githubusercontent.com/lemonrock/css/master/COPYRIGHT. No part of predicator, including this file, may be copied, modified, propagated, or distributed except according to the terms contained in the COPYRIGHT file.
// Copyright © 2017 The developers of css. See the COPYRIGHT file in the top-level directory of this distribution and at https://raw.githubusercontent.com/lemonrock/css/master/COPYRIGHT.


/// A `@document` rule's condition.
///
/// https://www.w3.org/TR/2012/WD-css3-conditional-20120911/#at-document
///
/// The `@document` rule's condition is written as a comma-separated list of URL matching functions, and the condition evaluates to true whenever any one of those functions evaluates to true.
#[derive(Clone, Debug)]
pub struct DocumentCondition(pub Vec<UrlMatchingFunction>);

impl ToCss for DocumentCondition
{
	fn to_css<W: fmt::Write>(&self, dest: &mut W) -> fmt::Result
	{
		let mut iter = self.0.iter();
		let first = iter.next().expect("Empty DocumentCondition, should contain at least one URL matching function");
		first.to_css(dest)?;
		for url_matching_function in iter
		{
			dest.write_str(", ")?;
			url_matching_function.to_css(dest)?;
		}
		Ok(())
	}
}

impl DocumentCondition
{
	/// Parse a document condition.
	pub(crate) fn parse<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>) -> Result<Self, ParseError<'i, CustomParseError<'i>>>
	{
		input.parse_comma_separated(|input| UrlMatchingFunction::parse(context, input)).map(DocumentCondition)
	}
	
	/// Evaluate a document condition.
	pub fn evaluate<D: Document>(&self, document: &D) -> bool
	{
		self.0.iter().any(|ref url_matching_function| url_matching_function.evaluate(document)	)
	}
}