Home
HCL Domino Designer User Guide and Reference
This guide provides information on using HCL Domino Designer and programming language reference information.
LotusScript® Language
Welcome to the LotusScript® Language section of Domino® Designer Help.
Error Processing
This chapter describes error processing in the LotusScript® language.
Run-time error processing
A run-time error occurs either when executing a statement results in an error or when LotusScript® executes an Error statement.
Informational functions used in run-time errors
The functions Err, Erl, Error, and Error$ describe the current error, if there is one. LotusScript® assigns a value to each of these functions when an error occurs.

HCL Domino Designer User Guide and Reference
This guide provides information on using HCL Domino Designer and programming language reference information.
- What's new in Domino Designer 14.5?
  The following features are new for developers in HCL Domino® Designer 14.5.
- What's new in Nomad Designer?
  HCL Nomad for web browsers v1.0.10 introduces the capability to design Notes databases. For more information, see HCL Nomad for web browsers User Documentation, Nomad web Designer.
- Accessibility and keyboard shortcuts
  Accessibility features assist users who have a disability, such as restricted mobility or limited vision, to use information technology content successfully.
- Application Design
  Welcome to the Application Design section of Domino® Designer Help.
- Application Management
  Welcome to the Application Management section of Domino® Designer Help.
- Domino® Query Language
  Domino® Query Language (DQL) is a facility running on a Domino server that provides a terse, shorthand syntax for finding documents. It supports a wide variety and complexity of search terms. It leverages existing design elements, avoiding the need to write detailed code to access them. DQL consolidates all methods in Domino for searching document contents.
- Composite Applications - Design and Management
  Composite applications are a key element in a service-oriented architecture (SOA) and contextual collaboration strategy. The ability to create and edit composite applications lets you easily integrate different types of components and technologies.
- DB2® Access views
  Domino® Designer includes two types of design elements to assist you in managing data contained in DB2® enabled Notes® databases:
- Programming Overview and User Interface
  This section contains general guidelines and examples that show where to use Java, LotusScript, and the formula language.
- Formula Language
  This section documents the formula language.
- LotusScript® Language
  Welcome to the LotusScript® Language section of Domino® Designer Help.
  - Introduction to LotusScript®
    This chapter introduces LotusScript® and describes, in general terms, how to use the script editor to write and modify scripts, how to compile scripts, and how to use the debugger to locate problems in the logic of your applications.
  - Script and Statement Construction Rules
    This chapter describes the rules for writing the basic elements of a script in the LotusScript® language.
  - Data Types, Constants, and Variables
    This chapter provides information about LotusScript® constants and variables and the data types of the values that they can represent.
  - Expressions and Operators
    This chapter describes the set of LotusScript® operators, how they may be combined with operands to form expressions, and how those expressions are evaluated.
  - Procedures: Functions, Subs, and Properties
  - File Handling
    This chapter describes file handling in the LotusScript® language.
  - Error Processing
    This chapter describes error processing in the LotusScript® language.
    - Types of errors
      LotusScript® recognizes two kinds of errors:
    - Run-time error processing
      A run-time error occurs either when executing a statement results in an error or when LotusScript® executes an Error statement.
      - Informational functions used in run-time errors
        The functions Err, Erl, Error, and Error$ describe the current error, if there is one. LotusScript® assigns a value to each of these functions when an error occurs.
        Using the informational functions
        These examples show how LotusScript® manages the error number, its associated error message, and its line number.
      - Statements used in run-time errors
        You include statements in a script to explicitly manage the flow of control when an error occurs.
  - User-Defined Data Types and Classes
    This chapter describes two kinds of custom data structures that you can define in LotusScript®. Each can hold data of different types in a single data structure.
  - Managing Flow in Scripts
    The flow of execution of a script generally follows the sequence of statements in the script. This chapter describes the behavior of particular statements that alter the flow of execution.
  - Managing Asynchronous Web Agents in Domino®
    This chapter describes how to use multiple threads and synchronization to manage HTTP agents with Domino®.
  - Beyond Core LotusScript®
    This chapter discusses the role that LotusScript® plays with HCL products, your operating environment, other programs, and interactive user applications.
  - LotusScript® Language Reference
    This chapter describes the use of statements, built-in functions, subs, data types, and directives in the LotusScript® language.
  - Language and Script Limits
    This appendix describes LotusScript® language limits of several kinds: for example, the legal ranges in data representation, the limits on numerical specifications within statements, and the maximum number of different kinds of elements that can be defined in a script.
  - Platform Differences
    The LotusScript® language and functionality on the UNIX™ platform, the Macintosh platform, and the IBM i® platform differ in various ways from the language and functionality described in the rest of this language reference. This appendix describes the differences.
  - LotusScript/REXX Integration
    This appendix provides an overview of REXX integration in the LotusScript® language.
  - LotusScript® Aliases
    This appendix lists the LotusScript® aliases and their equivalent text.
  - MIME Charset Names
  - Compile-time Error Messages
    This chapter describes the compile-time error messages in the LotusScript® language.
  - Run-time Error Messages
    This chapter describes the run-time error messages in the LotusScript® language.
- LotusScript/COM/OLE Classes
- Java/CORBA Classes
  This section documents the Java/CORBA classes.
- Connectors
  Connectors provide native access to a wide variety of DBMS products, ODBC, the platform File system, Enterprise Resource Planning systems, and Transaction Processing systems.
- Javadoc™ for Domino® Designer related APIs
  As part of providing additional Java™ reference documentation, Domino® Designer ships with a help plugin that contains Javadoc™ for additional Domino Designer related APIs.

Informational functions used in run-time errors

The functions Err, Erl, Error, and Error$ describe the current error, if there is one. LotusScript® assigns a value to each of these functions when an error occurs.

Err function
Returns the LotusScript® error number for the current error, or the number you specify with the Err statement. If there is no current error, Err returns FALSE (0). The value of the function Err persists across scripts. Completing execution of a script does not automatically reset this function's value to 0. The value of Err is reset to 0 only by an Err statement or a Resume statement.
Erl function
Returns the current line number within the procedure where the error handler is defined.
Error and Error$ functions
Return the error message for the current error, or the message for the error number you specify with the Err statement. If there is no current error, Error and Error$ return the empty string "".