var isDigit = require('../tokenizer').isDigit;
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var cmpChar = require('../tokenizer').cmpChar;
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var TYPE = require('../tokenizer').TYPE;
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var DELIM = TYPE.Delim;
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var WHITESPACE = TYPE.WhiteSpace;
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var COMMENT = TYPE.Comment;
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var IDENT = TYPE.Ident;
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var NUMBER = TYPE.Number;
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var DIMENSION = TYPE.Dimension;
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var PLUSSIGN = 0x002B; // U+002B PLUS SIGN (+)
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var HYPHENMINUS = 0x002D; // U+002D HYPHEN-MINUS (-)
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var N = 0x006E; // U+006E LATIN SMALL LETTER N (n)
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var DISALLOW_SIGN = true;
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var ALLOW_SIGN = false;
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function isDelim(token, code) {
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return token !== null && token.type === DELIM && token.value.charCodeAt(0) === code;
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}
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function skipSC(token, offset, getNextToken) {
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while (token !== null && (token.type === WHITESPACE || token.type === COMMENT)) {
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token = getNextToken(++offset);
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}
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return offset;
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}
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function checkInteger(token, valueOffset, disallowSign, offset) {
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if (!token) {
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return 0;
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}
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var code = token.value.charCodeAt(valueOffset);
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if (code === PLUSSIGN || code === HYPHENMINUS) {
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if (disallowSign) {
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// Number sign is not allowed
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return 0;
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}
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valueOffset++;
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}
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for (; valueOffset < token.value.length; valueOffset++) {
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if (!isDigit(token.value.charCodeAt(valueOffset))) {
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// Integer is expected
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return 0;
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}
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}
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return offset + 1;
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}
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// ... <signed-integer>
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// ... ['+' | '-'] <signless-integer>
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function consumeB(token, offset_, getNextToken) {
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var sign = false;
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var offset = skipSC(token, offset_, getNextToken);
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token = getNextToken(offset);
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if (token === null) {
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return offset_;
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}
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if (token.type !== NUMBER) {
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if (isDelim(token, PLUSSIGN) || isDelim(token, HYPHENMINUS)) {
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sign = true;
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offset = skipSC(getNextToken(++offset), offset, getNextToken);
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token = getNextToken(offset);
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if (token === null && token.type !== NUMBER) {
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return 0;
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}
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} else {
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return offset_;
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}
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}
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if (!sign) {
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var code = token.value.charCodeAt(0);
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if (code !== PLUSSIGN && code !== HYPHENMINUS) {
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// Number sign is expected
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return 0;
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}
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}
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return checkInteger(token, sign ? 0 : 1, sign, offset);
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}
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// An+B microsyntax https://www.w3.org/TR/css-syntax-3/#anb
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module.exports = function anPlusB(token, getNextToken) {
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/* eslint-disable brace-style*/
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var offset = 0;
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if (!token) {
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return 0;
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}
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// <integer>
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if (token.type === NUMBER) {
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return checkInteger(token, 0, ALLOW_SIGN, offset); // b
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}
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// -n
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// -n <signed-integer>
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// -n ['+' | '-'] <signless-integer>
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// -n- <signless-integer>
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// <dashndashdigit-ident>
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else if (token.type === IDENT && token.value.charCodeAt(0) === HYPHENMINUS) {
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// expect 1st char is N
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if (!cmpChar(token.value, 1, N)) {
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return 0;
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}
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switch (token.value.length) {
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// -n
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// -n <signed-integer>
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// -n ['+' | '-'] <signless-integer>
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case 2:
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return consumeB(getNextToken(++offset), offset, getNextToken);
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// -n- <signless-integer>
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case 3:
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if (token.value.charCodeAt(2) !== HYPHENMINUS) {
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return 0;
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}
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offset = skipSC(getNextToken(++offset), offset, getNextToken);
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token = getNextToken(offset);
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return checkInteger(token, 0, DISALLOW_SIGN, offset);
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// <dashndashdigit-ident>
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default:
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if (token.value.charCodeAt(2) !== HYPHENMINUS) {
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return 0;
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}
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return checkInteger(token, 3, DISALLOW_SIGN, offset);
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}
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}
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// '+'? n
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// '+'? n <signed-integer>
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// '+'? n ['+' | '-'] <signless-integer>
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// '+'? n- <signless-integer>
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// '+'? <ndashdigit-ident>
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else if (token.type === IDENT || (isDelim(token, PLUSSIGN) && getNextToken(offset + 1).type === IDENT)) {
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// just ignore a plus
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if (token.type !== IDENT) {
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token = getNextToken(++offset);
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}
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if (token === null || !cmpChar(token.value, 0, N)) {
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return 0;
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}
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switch (token.value.length) {
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// '+'? n
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// '+'? n <signed-integer>
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// '+'? n ['+' | '-'] <signless-integer>
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case 1:
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return consumeB(getNextToken(++offset), offset, getNextToken);
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// '+'? n- <signless-integer>
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case 2:
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if (token.value.charCodeAt(1) !== HYPHENMINUS) {
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return 0;
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}
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offset = skipSC(getNextToken(++offset), offset, getNextToken);
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token = getNextToken(offset);
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return checkInteger(token, 0, DISALLOW_SIGN, offset);
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// '+'? <ndashdigit-ident>
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default:
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if (token.value.charCodeAt(1) !== HYPHENMINUS) {
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return 0;
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}
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return checkInteger(token, 2, DISALLOW_SIGN, offset);
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}
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}
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// <ndashdigit-dimension>
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// <ndash-dimension> <signless-integer>
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// <n-dimension>
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// <n-dimension> <signed-integer>
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// <n-dimension> ['+' | '-'] <signless-integer>
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else if (token.type === DIMENSION) {
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var code = token.value.charCodeAt(0);
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var sign = code === PLUSSIGN || code === HYPHENMINUS ? 1 : 0;
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for (var i = sign; i < token.value.length; i++) {
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if (!isDigit(token.value.charCodeAt(i))) {
|
break;
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}
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}
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if (i === sign) {
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// Integer is expected
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return 0;
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}
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if (!cmpChar(token.value, i, N)) {
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return 0;
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}
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// <n-dimension>
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// <n-dimension> <signed-integer>
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// <n-dimension> ['+' | '-'] <signless-integer>
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if (i + 1 === token.value.length) {
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return consumeB(getNextToken(++offset), offset, getNextToken);
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} else {
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if (token.value.charCodeAt(i + 1) !== HYPHENMINUS) {
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return 0;
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}
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// <ndash-dimension> <signless-integer>
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if (i + 2 === token.value.length) {
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offset = skipSC(getNextToken(++offset), offset, getNextToken);
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token = getNextToken(offset);
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return checkInteger(token, 0, DISALLOW_SIGN, offset);
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}
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// <ndashdigit-dimension>
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else {
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return checkInteger(token, i + 2, DISALLOW_SIGN, offset);
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}
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}
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}
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return 0;
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};
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