Welcome
Reference
This documentation provides HCL Link reference information.
Functions and Expressions
Use HCL Link functions and expressions to create component rules and map rules.
Expressions and evaluations
The documentation provided here describes HCL Link functions and expressions. Functions and expressions are used to create component rules and map rules.
Expressions that evaluate to NONE
The following discussion explains how the map designer evaluates an expression when expressions within it evaluate to "none".

Introduction
Congratulations on your selection of HCL Link as your data integration solution!
What's new
Learn about the new and changed functions and features in HCL Link version 1.3.2.0.
Release notes
Read the latest release specific information for HCL Link version 1.3.2.0.
System requirements
A complete desciption of the hardware and software requirements for both Windows and Linux systems.
Installation
Everything you need to know to install HCL Link.
Administration
Here you will find the tasks that are required for administration of your HCL Link product.
Projects
A project is a container for HCL Link artifacts.
Services
Service definitions define REST services and the endpoints of a service. This guide provides step-by-step instructions for creating, importing, and managing services using the system interface, following Microsoft standards.
Connectors
This documentation describes the connectors and how they are used.
Packages
Servers
This documentation contains a description of the server groups and servers.
Variables
The variables described here include Configuration variables, flow variables, and cache variables.
Dashboards
A description of HCL Link dashboards, including the Server dashboard and the Kibana dashboard.
Runtimes
Descriptions of Link runtime services.
Resource Adapters
About the HCL Link Resource Adapters, and how to use them.
Cloud Native Link
Cloud Native Link refers to the HCL Link product installation on a Kubernetes cluster.
Reference
This documentation provides HCL Link reference information.
- Functions and Expressions
  Use HCL Link functions and expressions to create component rules and map rules.
  - Expressions and evaluations
    The documentation provided here describes HCL Link functions and expressions. Functions and expressions are used to create component rules and map rules.
    - Expressions
      An expression is a statement about data objects. Expressions are used in component rules in the schema designer and in map rules in the map designer.
    - Literals
      A literal is a constant value. A literal may be a number or a text string.
    - Data object names
      A data object is referenced in an expression by its name.
    - Evaluating expressions
      Expressions are evaluated based on the context in which data object names, literals, operators, function names and map names appear in the expression, and the data on which it operates. .
    - Operators
      Operators are used for arithmetic functions and text functions on items.
    - Using functions in expressions
      Functions perform a particular action on its input arguments.
    - Map names in expressions
      Map names in expressions that are used in map rules represent calls to functional maps.
    - Expressions that evaluate to NONE
      The following discussion explains how the map designer evaluates an expression when expressions within it evaluate to "none".
      - When an operand evaluates to NONE
        The following table explains how an operator expression evaluates when an operand evaluates to none.
      - When an input argument of a function evaluates to NONE
        If any input argument of a function evaluates to "none", the function might not evaluate to "none".
      - When an input argument of a functional map evaluates to NONE
        If any argument of a functional map evaluates to "none", the functional map will not be evaluated for that evaluation set.
      - When an input of an executable map evaluates to NONE
        The evaluation of a map referenced in an expression differs from the evaluation of that map when it is executed as a functional map and the evaluation of a function because of how the NONE is treated.
      - Impact of track setting on order of output
        This property setting determines whether objects are tracked according to content or according to their position within a series.
    - Evaluated expressions assigned to output items
      When an output item is defined, then it is determined from the result of the evaluated expression.
    - Automatic item format conversions
      When an item is assigned an output value, the map designer will automatically convert an item with the same interpretation (either number, text, date, or time) from one presentation to another.
  - Using functions
    A function is an expression that generates an output by performing a certain operation on one or more inputs.
  - Syntax of a function
    The following is an example of a function:
  - Function argument syntax
    Arguments typically have some restrictions on the expression used for that argument.
  - Character-set encoding functions
    Functions that use the HCL Link EXIT architecture convert data to the native character set of the platform as part of the function call.
  - General functions
    There are several general functions you can call from map rule to process input.
  - Bidirectional functions
    Bidirectional languages such as Arabic and Hebrew are languages in which the text is presented to the user ordered from right to left, but numbers and Latin alphabetic strings within the text are presented left to right.
  - Bit manipulation and testing functions
    You can use this function to manipulate and to test a bit in a binary number.
  - Cache functions
    Use cache functions to specify a value for each of the cache variables defined for a flow, and additionally, to alter an already specified value for a cache variable.
  - Conversion functions
    You can use this function to convert an expression from one datatype to another datatype.
  - Date/time functions
    You can use this function to perform various operations on date and time.
  - Error handling functions
    You can use this function in evaluating the type of error during map execution.
  - External interface functions
    You can use this function to retrieve data from a database from within in a map rule.
  - Flow functions
    Use Flow functions to specify a value for each of the flow variables defined for a flow, and additionally, to alter an already specified value for a flow variable.
  - Inspection functions
    You can use this function to test and inspect the object.
  - Logical functions
    Logical functions provide a way to use logical conditions to display one of several values.
  - Lookup and reference functions
    These function search operates by scanning the appropriate set of items in sequence, attempting to match the logical condition.
  - Math and statistics functions
    Precede all MATHLIB functions with mathlib->
  - Text functions
    These functions are used to convert the text item in a map rule.
  - XML functions
    There are several XML functions that you can call from component rules and map rules to process input XML data.
  - Custom functions
    From the Type Designer or Map Designer, you can create custom functions to call external libraries.
  - Date and time format strings
    You can use the listed format strings for numbers, dates and times in functions such as the CURRENTDATETIME, FROMNUMBER, TONUMBER, FROMDATETIME, and TODATETIME.
  - Number format strings
    You can create custom number formats by using the given format strings.
  - RUN function return codes
    The RUN function return codes and messages might result when using the RUN function.
  - Character set codes for CPACKAGE, CSERIESTOTEXT, and CTEXT
    The second argument of the CPACKAGE, CSERIESTOTEXT, and CTEXT functions specifies the character set of the output of the function. The value of the second argument (the character set of the object content), must be a valid character set code.
Notices

Expressions that evaluate to NONE

The following discussion explains how the map designer evaluates an expression when expressions within it evaluate to "none".