|
Lift Framework example source code file (CssSelector.scala)
The Lift Framework CssSelector.scala source code/* * Copyright 2011 WorldWide Conferencing, LLC * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package net.liftweb package util import scala.util.parsing.combinator.{Parsers, ImplicitConversions} import scala.xml.NodeSeq import net.liftweb.common._ sealed trait CssSelector { def subNodes: Box[SubNode] } final case class ElemSelector(elem: String, subNodes: Box[SubNode]) extends CssSelector final case class StarSelector(subNodes: Box[SubNode]) extends CssSelector final case class IdSelector(id: String, subNodes: Box[SubNode]) extends CssSelector final case class ClassSelector(clss: String, subNodes: Box[SubNode]) extends CssSelector final case class NameSelector(name: String, subNodes: Box[SubNode]) extends CssSelector final case class AttrSelector(name: String, value: String, subNodes: Box[SubNode]) extends CssSelector sealed trait SubNode object SubNode { def unapply(bind: CssBind): Option[Box[SubNode]] = Some(bind.css.flatMap(_.subNodes)) } sealed trait WithKids { def transform(original: NodeSeq, newNs: NodeSeq): NodeSeq } final case class KidsSubNode() extends SubNode with WithKids { def transform(original: NodeSeq, newNs: NodeSeq): NodeSeq = newNs } final case class PrependKidsSubNode() extends SubNode with WithKids { def transform(original: NodeSeq, newNs: NodeSeq): NodeSeq = newNs ++ original } final case class AppendKidsSubNode() extends SubNode with WithKids { def transform(original: NodeSeq, newNs: NodeSeq): NodeSeq = original ++ newNs } sealed trait AttributeRule final case class AttrSubNode(attr: String) extends SubNode with AttributeRule final case class AttrAppendSubNode(attr: String) extends SubNode with AttributeRule final case class AttrRemoveSubNode(attr: String) extends SubNode with AttributeRule final case class SelectThisNode(kids: Boolean) extends SubNode /** * Parse a subset of CSS into the appropriate selector objects */ object CssSelectorParser extends Parsers with ImplicitConversions { private val cache = new LRUMap[String, CssSelector](25000) /** * Parse a String into a CSS Selector */ def parse(_toParse: String): Box[CssSelector] = synchronized { // trim off leading and trailing spaces val toParse = _toParse.trim // this method is synchronized because the Parser combinator is not // thread safe, so we'll only parse one at a time, but given that most // of the selectors will be cached, it's not really a performance hit cache.get(toParse) or { internalParse(toParse).map { sel => { // cache the result cache(toParse) = sel sel } } } } import scala.util.parsing.input.CharSequenceReader type Elem = Char type UnitParser=Parser[Unit] private def internalParse(toParse: String): Box[CssSelector] = { val reader: Input = new CharSequenceReader(toParse, 0) topParser(reader) match { case Success(v, _) => Full(v) case x => Empty } } private implicit def str2chars(s: String): List[Char] = new scala.collection.immutable.WrappedString(s).toList private lazy val topParser: Parser[CssSelector] = { phrase(idMatch | nameMatch | classMatch | attrMatch | elemMatch | starMatch | colonMatch) } private lazy val colonMatch: Parser[CssSelector] = ':' ~> id ~ opt(subNode) ^? { case "button" ~ sn => AttrSelector("type", "button", sn) case "checkbox" ~ sn => AttrSelector("type", "checkbox", sn) case "file" ~ sn => AttrSelector("type", "file", sn) case "password" ~ sn => AttrSelector("type", "password", sn) case "radio" ~ sn => AttrSelector("type", "radio", sn) case "reset" ~ sn => AttrSelector("type", "reset", sn) case "submit" ~ sn => AttrSelector("type", "submit", sn) case "text" ~ sn => AttrSelector("type", "text", sn) } private lazy val idMatch: Parser[CssSelector] = '#' ~> id ~ opt(subNode) ^^ { case id ~ sn => IdSelector(id, sn) } private lazy val nameMatch: Parser[CssSelector] = '@' ~> id ~ opt(subNode) ^^ { case name ~ sn => NameSelector(name, sn) } private lazy val elemMatch: Parser[CssSelector] = id ~ opt(subNode) ^^ { case elem ~ sn => ElemSelector(elem, sn) } private lazy val starMatch: Parser[CssSelector] = '*' ~> opt(subNode) ^^ { case sn => StarSelector(sn) } private lazy val id: Parser[String] = letter ~ rep(letter | number | '-' | '_' | ':' | '.') ^^ { case first ~ rest => (first :: rest).mkString } private def isLetter(c: Char): Boolean = c.isLetter private def isNumber(c: Char): Boolean = c.isDigit private lazy val letter: Parser[Char] = elem("letter", isLetter) private lazy val number: Parser[Char] = elem("number", isNumber) private lazy val classMatch: Parser[CssSelector] = '.' ~> attrName ~ opt(subNode) ^^ { case cls ~ sn => ClassSelector(cls, sn) } private lazy val attrMatch: Parser[CssSelector] = attrName ~ '=' ~ attrConst ~ opt(subNode) ^^ { case "id" ~ _ ~ const ~ sn => IdSelector(const, sn) case "name" ~ _ ~ const ~ sn => NameSelector(const, sn) case n ~ _ ~ v ~ sn => AttrSelector(n, v, sn) } private lazy val subNode: Parser[SubNode] = rep1(' ') ~> ((opt('*') ~ '[' ~> attrName <~ '+' ~ ']' ^^ { name => AttrAppendSubNode(name) }) | (opt('*') ~ '[' ~> attrName <~ '!' ~ ']' ^^ { name => AttrRemoveSubNode(name) }) | (opt('*') ~ '[' ~> attrName <~ ']' ^^ { name => AttrSubNode(name) }) | ('-' ~ '*' ^^ (a => PrependKidsSubNode())) | ('>' ~ '*' ^^ (a => PrependKidsSubNode())) | ('*' ~ '+' ^^ (a => AppendKidsSubNode())) | ('*' ~ '<' ^^ (a => AppendKidsSubNode())) | '*' ^^ (a => KidsSubNode()) | '^' ~ '*' ^^ (a => SelectThisNode(true)) | '^' ~ '^' ^^ (a => SelectThisNode(false))) private lazy val attrName: Parser[String] = (letter | '_' | ':') ~ rep(letter | number | '-' | '_' | ':' | '.') ^^ { case first ~ rest => (first :: rest).mkString } private lazy val attrConst: Parser[String] = { (('\'' ~> rep(elem("isValid", (c: Char) => { c != '\'' && c >= ' ' })) <~ '\'') ^^ { case s => s.mkString }) | (('"' ~> rep(elem("isValid", (c: Char) => { c != '"' && c >= ' ' })) <~ '"') ^^ { case s => s.mkString }) | (rep1(elem("isValid", (c: Char) => { c != '\'' && c != '"' && c > ' ' })) ^^ { case s => s.mkString }) } } Other Lift Framework examples (source code examples)Here is a short list of links related to this Lift Framework CssSelector.scala source code file: |
... this post is sponsored by my books ... | |
#1 New Release! |
FP Best Seller |
Copyright 1998-2021 Alvin Alexander, alvinalexander.com
All Rights Reserved.
A percentage of advertising revenue from
pages under the /java/jwarehouse
URI on this website is
paid back to open source projects.