Method getExpression

parser/parser.go:709–753

getExpression - Return proper structure of ast.Expression and validate the syntax Available expressions: - ast.OperationExpression - ast.BooleanExpression - ast.ConditionExpression - ast.ContainExpression

()

// - ast.ConditionExpression
// - ast.ContainExpression
func (parser *Parser) getExpression() (bool, ast.Expression, error) {

	if parser.currentToken.Type == token.IDENT ||
		parser.currentToken.Type == token.LITERAL ||
		parser.currentToken.Type == token.NULL ||
		parser.currentToken.Type == token.APOSTROPHE ||
		parser.currentToken.Type == token.TRUE ||
		parser.currentToken.Type == token.FALSE {

		leftSide, isAnonymitifier, err := parser.getExpressionLeftSideValue()
		if err != nil {
			return false, nil, err
		}

		isValidExpression := false
		var expression ast.Expression

		if parser.currentToken.Type == token.EQUAL || parser.currentToken.Type == token.NOT {
			isValidExpression, expression, err = parser.getConditionalExpression(leftSide, isAnonymitifier)
		} else if parser.currentToken.Type == token.IN || parser.currentToken.Type == token.NOTIN {
			isValidExpression, expression, err = parser.getContainExpression(leftSide, isAnonymitifier)
		} else if leftSide.Type == token.TRUE || leftSide.Type == token.FALSE {
			expression = &ast.BooleanExpression{Boolean: leftSide}
			isValidExpression = true
			err = nil
		}

		if err != nil {
			return false, nil, err
		}

		if (parser.currentToken.Type == token.AND || parser.currentToken.Type == token.OR) && isValidExpression {
			isValidExpression, expression, err = parser.getOperationExpression(expression)
		}

		if err != nil {
			return false, nil, err
		}

		if isValidExpression {
			return true, expression, nil
		}
	}
	return false, nil, nil
}

func (parser *Parser) getExpressionLeftSideValue() (token.Token, bool, error) {
	var leftSide token.Token