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/*! https://mths.be/he v<%= version %> by @mathias | MIT license */
;(function(root) {

	// Detect free variables `exports`.
	var freeExports = typeof exports == 'object' && exports;

	// Detect free variable `module`.
	var freeModule = typeof module == 'object' && module &&
		module.exports == freeExports && module;

	// Detect free variable `global`, from Node.js or Browserified code,
	// and use it as `root`.
	var freeGlobal = typeof global == 'object' && global;
	if (freeGlobal.global === freeGlobal || freeGlobal.window === freeGlobal) {
		root = freeGlobal;
	}

	/*--------------------------------------------------------------------------*/

	// All astral symbols.
	var regexAstralSymbols = /<%= regexAstralSymbol %>/g;
	// All ASCII symbols (not just printable ASCII) except those listed in the
	// first column of the overrides table.
	// https://html.spec.whatwg.org/multipage/syntax.html#table-charref-overrides
	var regexAsciiWhitelist = /<%= regexAsciiWhitelist %>/g;
	// All BMP symbols that are not ASCII newlines, printable ASCII symbols, or
	// code points listed in the first column of the overrides table on
	// https://html.spec.whatwg.org/multipage/syntax.html#table-charref-overrides.
	var regexBmpWhitelist = /<%= regexBmpWhitelist %>/g;

	var regexEncodeNonAscii = /<%= regexEncodeNonAscii %>/g;
	var encodeMap = <%= encodeMap %>;

	var regexEscape = /["&'<>`]/g;
	var escapeMap = {
		'"': '&quot;',
		'&': '&amp;',
		'\'': '&#x27;',
		'<': '&lt;',
		// See https://mathiasbynens.be/notes/ambiguous-ampersands: in HTML, the
		// following is not strictly necessary unless it’s part of a tag or an
		// unquoted attribute value. We’re only escaping it to support those
		// situations, and for XML support.
		'>': '&gt;',
		// In Internet Explorer ≤ 8, the backtick character can be used
		// to break out of (un)quoted attribute values or HTML comments.
		// See http://html5sec.org/#102, http://html5sec.org/#108, and
		// http://html5sec.org/#133.
		'`': '&#x60;'
	};

	var regexInvalidEntity = /&#(?:[xX][^a-fA-F0-9]|[^0-9xX])/;
	var regexInvalidRawCodePoint = /<%= regexInvalidRawCodePoints %>/;
	var regexDecode = /<%=
		regexDecimalEscapeSource
	%>|<%=
		regexHexadecimalEscapeSource
	%>|<%=
		regexNamedReferenceSource
	%>|<%=
		regexLegacyReferenceSource
	%>/g;
	var decodeMap = <%= decodeMap %>;
	var decodeMapLegacy = <%= decodeMapLegacy %>;
	var decodeMapNumeric = <%= decodeMapOverrides %>;
	var invalidReferenceCodePoints = <%= invalidReferenceCodePoints %>;

	/*--------------------------------------------------------------------------*/

	var stringFromCharCode = String.fromCharCode;

	var object = {};
	var hasOwnProperty = object.hasOwnProperty;
	var has = function(object, propertyName) {
		return hasOwnProperty.call(object, propertyName);
	};

	var contains = function(array, value) {
		var index = -1;
		var length = array.length;
		while (++index < length) {
			if (array[index] == value) {
				return true;
			}
		}
		return false;
	};

	var merge = function(options, defaults) {
		if (!options) {
			return defaults;
		}
		var result = {};
		var key;
		for (key in defaults) {
			// A `hasOwnProperty` check is not needed here, since only recognized
			// option names are used anyway. Any others are ignored.
			result[key] = has(options, key) ? options[key] : defaults[key];
		}
		return result;
	};

	// Modified version of `ucs2encode`; see https://mths.be/punycode.
	var codePointToSymbol = function(codePoint, strict) {
		var output = '';
		if ((codePoint >= 0xD800 && codePoint <= 0xDFFF) || codePoint > 0x10FFFF) {
			// See issue #4:
			// “Otherwise, if the number is in the range 0xD800 to 0xDFFF or is
			// greater than 0x10FFFF, then this is a parse error. Return a U+FFFD
			// REPLACEMENT CHARACTER.”
			if (strict) {
				parseError('character reference outside the permissible Unicode range');
			}
			return '\uFFFD';
		}
		if (has(decodeMapNumeric, codePoint)) {
			if (strict) {
				parseError('disallowed character reference');
			}
			return decodeMapNumeric[codePoint];
		}
		if (strict && contains(invalidReferenceCodePoints, codePoint)) {
			parseError('disallowed character reference');
		}
		if (codePoint > 0xFFFF) {
			codePoint -= 0x10000;
			output += stringFromCharCode(codePoint >>> 10 & 0x3FF | 0xD800);
			codePoint = 0xDC00 | codePoint & 0x3FF;
		}
		output += stringFromCharCode(codePoint);
		return output;
	};

	var hexEscape = function(codePoint) {
		return '&#x' + codePoint.toString(16).toUpperCase() + ';';
	};

	var decEscape = function(codePoint) {
		return '&#' + codePoint + ';';
	};

	var parseError = function(message) {
		throw Error('Parse error: ' + message);
	};

	/*--------------------------------------------------------------------------*/

	var encode = function(string, options) {
		options = merge(options, encode.options);
		var strict = options.strict;
		if (strict && regexInvalidRawCodePoint.test(string)) {
			parseError('forbidden code point');
		}
		var encodeEverything = options.encodeEverything;
		var useNamedReferences = options.useNamedReferences;
		var allowUnsafeSymbols = options.allowUnsafeSymbols;
		var escapeCodePoint = options.decimal ? decEscape : hexEscape;

		var escapeBmpSymbol = function(symbol) {
			return escapeCodePoint(symbol.charCodeAt(0));
		};

		if (encodeEverything) {
			// Encode ASCII symbols.
			string = string.replace(regexAsciiWhitelist, function(symbol) {
				// Use named references if requested & possible.
				if (useNamedReferences && has(encodeMap, symbol)) {
					return '&' + encodeMap[symbol] + ';';
				}
				return escapeBmpSymbol(symbol);
			});
			// Shorten a few escapes that represent two symbols, of which at least one
			// is within the ASCII range.
			if (useNamedReferences) {
				string = string
					.replace(/&gt;\u20D2/g, '&nvgt;')
					.replace(/&lt;\u20D2/g, '&nvlt;')
					.replace(/&#x66;&#x6A;/g, '&fjlig;');
			}
			// Encode non-ASCII symbols.
			if (useNamedReferences) {
				// Encode non-ASCII symbols that can be replaced with a named reference.
				string = string.replace(regexEncodeNonAscii, function(string) {
					// Note: there is no need to check `has(encodeMap, string)` here.
					return '&' + encodeMap[string] + ';';
				});
			}
			// Note: any remaining non-ASCII symbols are handled outside of the `if`.
		} else if (useNamedReferences) {
			// Apply named character references.
			// Encode `<>"'&` using named character references.
			if (!allowUnsafeSymbols) {
				string = string.replace(regexEscape, function(string) {
					return '&' + encodeMap[string] + ';'; // no need to check `has()` here
				});
			}
			// Shorten escapes that represent two symbols, of which at least one is
			// `<>"'&`.
			string = string
				.replace(/&gt;\u20D2/g, '&nvgt;')
				.replace(/&lt;\u20D2/g, '&nvlt;');
			// Encode non-ASCII symbols that can be replaced with a named reference.
			string = string.replace(regexEncodeNonAscii, function(string) {
				// Note: there is no need to check `has(encodeMap, string)` here.
				return '&' + encodeMap[string] + ';';
			});
		} else if (!allowUnsafeSymbols) {
			// Encode `<>"'&` using hexadecimal escapes, now that they’re not handled
			// using named character references.
			string = string.replace(regexEscape, escapeBmpSymbol);
		}
		return string
			// Encode astral symbols.
			.replace(regexAstralSymbols, function($0) {
				// https://mathiasbynens.be/notes/javascript-encoding#surrogate-formulae
				var high = $0.charCodeAt(0);
				var low = $0.charCodeAt(1);
				var codePoint = (high - 0xD800) * 0x400 + low - 0xDC00 + 0x10000;
				return escapeCodePoint(codePoint);
			})
			// Encode any remaining BMP symbols that are not printable ASCII symbols
			// using a hexadecimal escape.
			.replace(regexBmpWhitelist, escapeBmpSymbol);
	};
	// Expose default options (so they can be overridden globally).
	encode.options = {
		'allowUnsafeSymbols': false,
		'encodeEverything': false,
		'strict': false,
		'useNamedReferences': false,
		'decimal' : false
	};

	var decode = function(html, options) {
		options = merge(options, decode.options);
		var strict = options.strict;
		if (strict && regexInvalidEntity.test(html)) {
			parseError('malformed character reference');
		}
		return html.replace(regexDecode, function($0, $1, $2, $3, $4, $5, $6, $7) {
			var codePoint;
			var semicolon;
			var decDigits;
			var hexDigits;
			var reference;
			var next;
			if ($1) {
				// Decode decimal escapes, e.g. `&#119558;`.
				decDigits = $1;
				semicolon = $2;
				if (strict && !semicolon) {
					parseError('character reference was not terminated by a semicolon');
				}
				codePoint = parseInt(decDigits, 10);
				return codePointToSymbol(codePoint, strict);
			}
			if ($3) {
				// Decode hexadecimal escapes, e.g. `&#x1D306;`.
				hexDigits = $3;
				semicolon = $4;
				if (strict && !semicolon) {
					parseError('character reference was not terminated by a semicolon');
				}
				codePoint = parseInt(hexDigits, 16);
				return codePointToSymbol(codePoint, strict);
			}
			if ($5) {
				// Decode named character references with trailing `;`, e.g. `&copy;`.
				reference = $5;
				if (has(decodeMap, reference)) {
					return decodeMap[reference];
				} else {
					// Ambiguous ampersand. https://mths.be/notes/ambiguous-ampersands
					if (strict) {
						parseError(
							'named character reference was not terminated by a semicolon'
						);
					}
					return $0;
				}
			}
			// If we’re still here, it’s a legacy reference for sure. No need for an
			// extra `if` check.
			// Decode named character references without trailing `;`, e.g. `&amp`
			// This is only a parse error if it gets converted to `&`, or if it is
			// followed by `=` in an attribute context.
			reference = $6;
			next = $7;
			if (next && options.isAttributeValue) {
				if (strict && next == '=') {
					parseError('`&` did not start a character reference');
				}
				return $0;
			} else {
				if (strict) {
					parseError(
						'named character reference was not terminated by a semicolon'
					);
				}
				// Note: there is no need to check `has(decodeMapLegacy, reference)`.
				return decodeMapLegacy[reference] + (next || '');
			}
		});
	};
	// Expose default options (so they can be overridden globally).
	decode.options = {
		'isAttributeValue': false,
		'strict': false
	};

	var escape = function(string) {
		return string.replace(regexEscape, function($0) {
			// Note: there is no need to check `has(escapeMap, $0)` here.
			return escapeMap[$0];
		});
	};

	/*--------------------------------------------------------------------------*/

	var he = {
		'version': '<%= version %>',
		'encode': encode,
		'decode': decode,
		'escape': escape,
		'unescape': decode
	};

	// Some AMD build optimizers, like r.js, check for specific condition patterns
	// like the following:
	if (
		typeof define == 'function' &&
		typeof define.amd == 'object' &&
		define.amd
	) {
		define(function() {
			return he;
		});
	}	else if (freeExports && !freeExports.nodeType) {
		if (freeModule) { // in Node.js, io.js, or RingoJS v0.8.0+
			freeModule.exports = he;
		} else { // in Narwhal or RingoJS v0.7.0-
			for (var key in he) {
				has(he, key) && (freeExports[key] = he[key]);
			}
		}
	} else { // in Rhino or a web browser
		root.he = he;
	}

}(this));