Constant

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Constant

In french: Constante

The constants are language elements whose value is fixed once and for all. This value cannot be modified during the execution of the program.

Example

CONSTANT
VATRate = 20
END

Syntax

Declaring one or more constants Hide the details

CONSTANT
<Name of Constant 1> = <Value 1>
<Name of Constant 2> = <Value 2>
END

<CONSTANT>:

Marks the beginning of the declaration of constants.

<Name of Constant>:

Name of constant to declare.

<Value>:

Value of the constant.

<END>:

Marks the end of the declaration of constants.

Remarks

Declaring the constants

The constants must be declared in:

The initialization code of project in order to be used in all the processes of the project (codes of project, codes of windows, codes of controls, procedures, ...).
The declaration code of global variables of a window in order to be used in all the processes of the window (code of window, codes of controls found in the window, local procedures, ...).
The opening code of a report in order to be used in all the processes of the report (codes of report, code of controls found in the report, local procedures, ...).
The declaration code of a class in order to be used in the class.
- To access this constant from a method of the class, use the syntax "::<Constant name>".
- To access this constant from a code external to the class, use the following syntax "<Class name>::<Constant name>".
The page loading code to be usable in all the browser processes of the page.

Remark: A constant is always global:

Remark: A constant declared in server code can be used in browser code.

Limits: Declaring a constant member

A constant member cannot be declared in:

Limits: Declaring constants with the same name

Several elements (variables or constants) with the same name cannot be declared in the same process.
If a constant and a variable have the same name in the same project:
- the variable will be used in the process where it was declared and in all the linked processes.
  For example, the variable is declared in the click code of a button. When clicking this button, this variable is passed as parameter to a local procedure. This variable will be used in this local procedure.
- the constant will be used in all the other processes.
If a constant "global" to the project and a constant "global" to a window have the same name:
- the constant "global" to the window will be used in all the processes of the window and window controls as well as in the "local" procedures of the window.
- the constant "global" to the project will be used in all the other processes.