Method _factor

src/maths/Parser.js:125–150

()

    }

    _factor() {
        let expression;
        let factor;
        let value;
        switch (this.token.type) {
            case 'num':
                value = this.token.value;
                this.token = this.lexer.getNextToken(this.decimalCharacter);

                return ASTNode.createLeaf(value);
            case '-':
                this.token = this.lexer.getNextToken(this.decimalCharacter);
                factor = this._factor();

                return ASTNode.createUnaryNode(factor);
            case '(':
                this.token = this.lexer.getNextToken(this.decimalCharacter);
                expression = this._exp();
                this._match(')');

                return expression;
            default: {
                throw new Error(`Unexpected token '${this.token.symbol}' with type '${this.token.type}' at position '${this.token.index}' in the factor function`);
            }
        }
    }

    _match(expected) {
        const index = this.lexer.getIndex() - 1;