import FrontCalculatorParserToken from "./front.calculator.parser.token"; import FrontCalculatorSymbolNumber from "../symbol/front.calculator.symbol.number"; import FrontCalculatorSymbolOpeningBracket from "../symbol/brackets/front.calculator.symbol.opening.bracket"; import FrontCalculatorSymbolClosingBracket from "../symbol/brackets/front.calculator.symbol.closing.bracket"; import FrontCalculatorSymbolFunctionAbstract from "../symbol/abstract/front.calculator.symbol.function.abstract"; import FrontCalculatorSymbolOperatorAbstract from "../symbol/abstract/front.calculator.symbol.operator.abstract"; import FrontCalculatorSymbolSeparator from "../symbol/front.calculator.symbol.separator"; import FrontCalculatorParserNodeSymbol from "./node/front.calculator.parser.node.symbol"; import FrontCalculatorParserNodeContainer from "./node/front.calculator.parser.node.container"; import FrontCalculatorParserNodeFunction from "./node/front.calculator.parser.node.function"; /** * The parsers has one important method: parse() * It takes an array of tokens as input and * returns an array of nodes as output. * These nodes are the syntax tree of the term. * */ export default class FrontCalculatorParser { /** * * @param {FrontCalculatorSymbolLoader} symbolLoader */ constructor(symbolLoader) { /** * * @type {FrontCalculatorSymbolLoader} */ this.symbolLoader = symbolLoader; } /** * Parses an array with tokens. Returns an array of nodes. * These nodes define a syntax tree. * * @param {FrontCalculatorParserToken[]} tokens * * @returns FrontCalculatorParserNodeContainer */ parse(tokens) { var symbolNodes = this.detectSymbols(tokens); var nodes = this.createTreeByBrackets(symbolNodes); nodes = this.transformTreeByFunctions(nodes); this.checkGrammar(nodes); // Wrap the nodes in an array node. return new FrontCalculatorParserNodeContainer(nodes); } /** * Creates a flat array of symbol nodes from tokens. * * @param {FrontCalculatorParserToken[]} tokens * @returns {FrontCalculatorParserNodeSymbol[]} */ detectSymbols(tokens) { var symbolNodes = []; var symbol = null; var identifier = null; var expectingOpeningBracket = false; // True if we expect an opening bracket (after a function name) var openBracketCounter = 0; for (var i = 0; i < tokens.length; i++) { var token = tokens[i]; var type = token.type; if (FrontCalculatorParserToken.TYPE_WORD === type) { identifier = token.value; symbol = this.symbolLoader.find(identifier); if (null === symbol) { throw ('Error: Detected unknown or invalid string identifier: ' + identifier + '.'); } } else if (type === FrontCalculatorParserToken.TYPE_NUMBER) { // Notice: Numbers do not have an identifier var symbolNumbers = this.symbolLoader.findSubTypes(FrontCalculatorSymbolNumber); if (symbolNumbers.length < 1 || !(symbolNumbers instanceof Array)) { throw ('Error: Unavailable number symbol processor.'); } symbol = symbolNumbers[0]; } else {// Type Token::TYPE_CHARACTER: identifier = token.value; symbol = this.symbolLoader.find(identifier); if (null === symbol) { throw ('Error: Detected unknown or invalid string identifier: ' + identifier + '.'); } if (symbol instanceof FrontCalculatorSymbolOpeningBracket) { openBracketCounter++; } if (symbol instanceof FrontCalculatorSymbolClosingBracket) { openBracketCounter--; // Make sure there are not too many closing brackets if (openBracketCounter < 0) { throw ('Error: Found closing bracket that does not have an opening bracket.'); } } } if (expectingOpeningBracket) { if (!(symbol instanceof FrontCalculatorSymbolOpeningBracket)) { throw ('Error: Expected opening bracket (after a function) but got something else.'); } expectingOpeningBracket = false; } else { if (symbol instanceof FrontCalculatorSymbolFunctionAbstract) { expectingOpeningBracket = true; } } var symbolNode = new FrontCalculatorParserNodeSymbol(token, symbol); symbolNodes.push(symbolNode); } // Make sure the term does not end with the name of a function but without an opening bracket if (expectingOpeningBracket) { throw ('Error: Expected opening bracket (after a function) but reached the end of the term'); } // Make sure there are not too many opening brackets if (openBracketCounter > 0) { throw ('Error: There is at least one opening bracket that does not have a closing bracket'); } return symbolNodes; } /** * Expects a flat array of symbol nodes and (if possible) transforms * it to a tree of nodes. Cares for brackets. * Attention: Expects valid brackets! * Check the brackets before you call this method. * * @param {FrontCalculatorParserNodeSymbol[]} symbolNodes * @returns {FrontCalculatorParserNodeAbstract[]} */ createTreeByBrackets(symbolNodes) { var tree = []; var nodesInBracket = []; // AbstractSymbol nodes inside level-0-brackets var openBracketCounter = 0; for (var i = 0; i < symbolNodes.length; i++) { var symbolNode = symbolNodes[i]; if (!(symbolNode instanceof FrontCalculatorParserNodeSymbol)) { throw ('Error: Expected symbol node, but got "' + symbolNode.constructor.name + '"'); } if (symbolNode.symbol instanceof FrontCalculatorSymbolOpeningBracket) { openBracketCounter++; if (openBracketCounter > 1) { nodesInBracket.push(symbolNode); } } else if (symbolNode.symbol instanceof FrontCalculatorSymbolClosingBracket) { openBracketCounter--; // Found a closing bracket on level 0 if (0 === openBracketCounter) { var subTree = this.createTreeByBrackets(nodesInBracket); // Subtree can be empty for example if the term looks like this: "()" or "functioname()" // But this is okay, we need to allow this so we can call functions without a parameter tree.push(new FrontCalculatorParserNodeContainer(subTree)); nodesInBracket = []; } else { nodesInBracket.push(symbolNode); } } else { if (0 === openBracketCounter) { tree.push(symbolNode); } else { nodesInBracket.push(symbolNode); } } } return tree; } /** * Replaces [a SymbolNode that has a symbol of type AbstractFunction, * followed by a node of type ContainerNode] by a FunctionNode. * Expects the $nodes not including any function nodes (yet). * * @param {FrontCalculatorParserNodeAbstract[]} nodes * * @returns {FrontCalculatorParserNodeAbstract[]} */ transformTreeByFunctions(nodes) { var transformedNodes = []; var functionSymbolNode = null; for (var i = 0; i < nodes.length; i++) { var node = nodes[i]; if (node instanceof FrontCalculatorParserNodeContainer) { var transformedChildNodes = this.transformTreeByFunctions(node.childNodes); if (null !== functionSymbolNode) { var functionNode = new FrontCalculatorParserNodeFunction(transformedChildNodes, functionSymbolNode); transformedNodes.push(functionNode); functionSymbolNode = null; } else { // not a function node.childNodes = transformedChildNodes; transformedNodes.push(node); } } else if (node instanceof FrontCalculatorParserNodeSymbol) { var symbol = node.symbol; if (symbol instanceof FrontCalculatorSymbolFunctionAbstract) { functionSymbolNode = node; } else { transformedNodes.push(node); } } else { throw ('Error: Expected array node or symbol node, got "' + node.constructor.name + '"'); } } return transformedNodes; } /** * Ensures the tree follows the grammar rules for terms * * @param {FrontCalculatorParserNodeAbstract[]} nodes */ checkGrammar(nodes) { // TODO Make sure that separators are only in the child nodes of the array node of a function node // (If this happens the calculator will throw an exception) for (var i = 0; i < nodes.length; i++) { var node = nodes[i]; if (node instanceof FrontCalculatorParserNodeSymbol) { var symbol = node.symbol; if (symbol instanceof FrontCalculatorSymbolOperatorAbstract) { var posOfRightOperand = i + 1; // Make sure the operator is positioned left of a (potential) operand (=prefix notation). // Example term: "-1" if (posOfRightOperand >= nodes.length) { throw ('Error: Found operator that does not stand before an operand.'); } var posOfLeftOperand = i - 1; var leftOperand = null; // Operator is unary if positioned at the beginning of a term if (posOfLeftOperand >= 0) { leftOperand = nodes[posOfLeftOperand]; if (leftOperand instanceof FrontCalculatorParserNodeSymbol) { if (leftOperand.symbol instanceof FrontCalculatorSymbolOperatorAbstract // example 1`+-`5 : + = operator, - = unary || leftOperand.symbol instanceof FrontCalculatorSymbolSeparator // example func(1`,-`5) ,= separator, - = unary ) { // Operator is unary if positioned right to another operator leftOperand = null; } } } // If null, the operator is unary if (null === leftOperand) { if (!symbol.operatesUnary) { throw ('Error: Found operator in unary notation that is not unary.'); } // Remember that this node represents a unary operator node.setIsUnaryOperator(true); } else { if (!symbol.operatesBinary) { console.log(symbol); throw ('Error: Found operator in binary notation that is not binary.'); } } } } else { this.checkGrammar(node.childNodes); } } } }.tx-content-switcher-toggle-switch-label{position:relative;display:inline-block;width:60px;height:34px}.tx-content-switcher-toggle-switch-label input{opacity:0;width:0;height:0}.tx-content-switcher-toggle-switch-slider{position:absolute;cursor:pointer;top:0;left:0;right:0;bottom:0;background-color:#ccc;-webkit-transition:.4s;transition:.4s;display:block;border-style:solid}.tx-content-switcher-toggle-switch-slider:before{position:absolute;content:"";height:26px;width:26px;left:0;top:50%;transform:translateY(-50%);background-color:#fff;-webkit-transition:.4s;transition:.4s}input:checked+.tx-content-switcher-toggle-switch-slider{background-color:#2196f3}input:focus+.tx-content-switcher-toggle-switch-slider{box-shadow:0 0 1px #2196f3}input:checked+.tx-content-switcher-toggle-switch-slider:before{-webkit-transform:translate(34px,-50%);-ms-transform:translate(34px,-50%);transform:translate(34px,-50%)}.tx-content-switcher-toggle-inner{display:flex;align-items:center;flex-direction:row;padding:30px 0}.tx-content-switcher-toggle.tx_switecher_left{justify-content:flex-start;display:flex}.tx-content-switcher-toggle.tx_switecher_center{justify-content:center;display:flex}.tx-content-switcher-toggle.tx_switecher_right{justify-content:flex-end;display:flex}.tx-content-switcher-toggle.tx_switecher_justify{display:block}.tx-content-switcher-toggle.tx_switecher_justify .tx-content-switcher-toggle-inner{justify-content:center}.tx-content-switcher-toggle-label-1,.tx-content-switcher-toggle-label-2{cursor:pointer} Comments on: Best Golf Gaming Sites & Apps to have On the internet Sportsbook Admirers https://makemyasset.in/?p=2539 Best Real Estate Firm in Gurgaon Sun, 09 Mar 2025 22:50:21 +0000 hourly 1 https://wordpress.org/?v=6.7.2