DEFINE VARIABLE statement

Defines a variable for use in one or more procedures, a variable data member of a class for use in a single class or class hierarchy, or by other classes and procedures, or a variable data element for use within a single class-based method.

Syntax

DEFINE {[[ NEW [ GLOBAL ]] SHARED ]| 
            [ PRIVATE | PROTECTED | PUBLIC ]
            [ STATIC ][ SERIALIZABLE | NON-SERIALIZABLE ]}
  VARIABLE variable-name
  {{   AS primitive-type-name 
       | AS [ CLASS ]{object-type-name}
       | LIKE field       }[ EXTENT [constant]]} 
  [ SERIALIZE-NAME serialize-name ]
  [ BGCOLOR expression]
  [ COLUMN-LABEL label]
  [ CONTEXT-HELP-ID expression]
  [ DCOLOR expression]
  [ DECIMALS n]
  [ DROP-TARGET ]
  [ FONT expression]
  [ FGCOLOR expression]
  [ FORMAT string]
  [ INITIAL
      { constant |{[ constant[ , constant]...]}}]
  [ LABEL string[ , string]...]
  [ MOUSE-POINTER expression]
  [ NO-UNDO ]
  [[ NOT ] CASE-SENSITIVE ]
  [ PFCOLOR expression]
  {[ view-as-phrase ]}
  {[ trigger-phrase ]}

NEW SHARED VARIABLE variable-name

Defines and identifies a variable to be shared by a procedure called directly or indirectly by the current procedure. The called procedure must name the same variable in a DEFINE SHARED VARIABLE statement.

NEW GLOBAL SHARED VARIABLE variable-name

Defines and identifies a variable that can be used by any procedure that names that variable using the DEFINE SHARED VARIABLE statement. The value of a global shared variable remains available throughout an ABL session.

SHARED VARIABLE variable-name

Defines and identifies a variable that was created by another procedure that used the DEFINE NEW SHARED VARIABLE or DEFINE NEW GLOBAL SHARED VARIABLE statement.

[ PRIVATE | PROTECTED | PUBLIC ][ STATIC ][ SERIALIZABLE | NON-SERIALIZABLE ] VARIABLE variable-name

Defines and identifies a variable as a data member of a class, and optionally specifies an access mode (PRIVATE, PROTECTED, or PUBLIC) and scope (instance or STATIC) for that data member, as well as whether or not the variable will participate in serialization (SERIALIZABLE or NON-SERIALIZABLE).

You cannot specify these options when defining a variable as a data element of a method (including constructors, destructors, and property accessors) or procedure.

Note: The specified options are applicable only when defining a data member for a class in a class definition (.cls) file. The PRIVATE/PROTECTED/PUBLIC modifier and the STATIC modifier can appear in either order, e.g., DEFINE STATIC PUBLIC VARIABLE myVariable... is valid syntax. Note also that you cannot shadow (override) the definition of a given variable data member in a class hierarchy.

PRIVATE variable data members can be accessed by the defining class. An instance can access a private data member of another instance if both instances are from the same class. PROTECTED variable data members can be accessed by the defining class and any of its derived classes. An instance can access a protected data member of another instance that is at the same level or higher in the class hierarchy. PUBLIC variable data members can be accessed by:

• The defining class
• Any of its derived classes
• Any class or procedure that has access to a class instance that defines or inherits the variable data member

Any piece of code can access a PUBLIC static variable data member. The default access mode is PRIVATE.

A variable defined with the STATIC option is a static data member of the class type for which it is defined and is scoped to the ABL session where it is referenced. ABL creates one copy of the specified class static variable on first reference to the class type, and ABL creates only one such copy for any number of instances of the class that you create. You can reference an accessible static variable data member in any piece of code.

Without the STATIC option, ABL creates an instance variable data member that is scoped to a single instance of the class where it is defined. ABL creates one copy of the specified instance variable for each such class instance that you create. You can reference any public instance variable in any procedure, or in any instance or static method defined inside or outside of the class where the instance variable is defined. Any static method can reference the public instance variable only using an object reference to a class instance that defines the variable as a data member. If the referencing static method is defined in the same class as the public instance variable, the class must instantiate itself in order to have access to an instance reference.

Note: In ABL, all PRIVATE and PROTECTED access modes are class based. An instance can access the PRIVATE member of another instance if both instances are from the same class. Likewise, a PROTECTED member can be accessed from any instance of the class or subclass that defines it. In other words, an instance can access a protected member of a second instance that is from the same level or higher in the class hierarchy.

For more information on the mechanism for accessing variable data members of different access modes and scopes, see the reference entry for Class-based data member access.

Note: Members of a class are grouped into six namespaces, including buffers/temp-tables, methods, variables/properties/events, ProDataSets, queries, and data-sources. Variables, properties, and events defined as members of a class share the same namespace. There can be only one class member in this namespace with a given name (not counting abstract member overrides).

Class-based objects that are defined as serializable (using the SERIALIZABLE option in the CLASS statement) can be passed as parameters in remotes call between the AppServer and ABL clients and can be serialized to binary or JSON format. By default, both passing a class as a parameter and serializing an object to binary via the Progress.IO.BinarySerializer class include all data members regardless of access mode. However, for JSON serialization via Progress.IO.JsonSerializer, only public data members are serialized. To include a protected or private property during JSON serialization, SERIALIZABLE must be added to the definition. See Serialize( ) method (JsonSerializer) for more information.

Use the NON-SERIALIZABLE option to exclude a given variable from the serialization process via the Progress.IO.BinarySerializer or Progress.IO.JsonSerializer class. A variable marked as NON-SERIALIZABLE is assigned its initial value when the class is deserialized.

You can also use the NON-SERIALIZALBE option to make a class that otherwise would not be serializable because one or more of its members. (See the Parameter passing syntax entry for full details on what can and cannot be serialized.) For example, if a variable itself is a class-based object that is not serializable, adding the NON-SERIALIZABLE keyword to that variable will allow the class that contains it to be defined as SERIALIZABLE.

Note: Use the SERIALIZABLE and NON-SERIALIZABLE options only with instance variables. These options are not for use with variables defined as STATIC or as part of an interface.

If variable-name is an ABL reserved keyword, you must include an access mode of PUBLIC, PROTECTED, or PRIVATE in its definition. You must also use the THIS-OBJECT system reference or Type-name syntax to access the variable data member. For more information on referencing variable data members, see the reference entry for Class-based data member access.

Note: If the data member is defined in a class that is derived from a .NET class, other restrictions on variable-name apply. For more information, see the CLASS statement reference entry.

For more information on where and how to define data members in a class, see the CLASS statement reference entry.

VARIABLE variable-name

Defines and identifies a variable whose value you can access only within the current procedure, method of a class (including constructors, destructors, and property accessors), or as a PRIVATE data member of a class.

AS primitive-type-name

Specifies a built-in primitive type for the variable you are defining. The built-in data type (primitive-type-name) can be one of the following:

CHARACTER | COM-HANDLE | DATE | DATETIME | DATETIME-TZ | DECIMAL | HANDLE | INT64 | INTEGER | LOGICAL | LONGCHAR | MEMPTR | RAW | RECID | ROWID

For more information on these primitive types, see the Data types reference entry.

AS [ CLASS ]{object-type-name}

Defines the variable as an object reference with the data type of a class or interface. The default value of the variable is the Unknown value (?). You cannot assign an initial value using the INITIAL option.

object-type-name

Specifies the type name of an ABL or .NET class or interface. Specify an object type name using the syntax described in the Type-name syntax reference entry. With an appropriate USING statement, you can also specify a class or interface name alone, without the qualifying package or namespace.

You cannot directly specify the type name of a .NET mapped object type (such as System.Int32). To define a variable that matches a .NET mapped type, you must define it as the corresponding ABL primitive type (primitive-type-name).

CLASS

If the specified class or interface type name conflicts with an abbreviation for a built-in primitive type name, such as INT for INTEGER, you must specify the CLASS keyword.

For more information on object references, see the Class-based object reference reference entry.

LIKE field

Indicates the name of the variable, database field, temp-table field, or work table field whose characteristics you want to use for the variable you are defining. If you name a variable with this option, you must have defined that variable earlier in the procedure. You can override the format, label, initial value, decimals, and extent of the variable or database field by using the FORMAT, LABEL, COLUMN-LABEL, INITIAL, DECIMALS, EXTENT, and VIEW-AS options. If you do not use these options, the variable takes on the characteristics of the variable or database field you name.

If field has help and validate options defined, the variable you are defining does not inherit those characteristics.

If you reference a database field in a LIKE option in a DEFINE VARIABLE statement, DEFINE TEMP-TABLE statement, DEFINE WORK-TABLE statement, or format phrase, the database containing the referenced field must be connected at compile time but not necessarily at run time. Therefore, use the LIKE option with caution.

EXTENT [constant ]

Defines the variable as an array of data elements, where the element data type is specified by the AS primitive-type-name option, the LIKE field option, or the AS object-type-name option. This option can specify an array variable as either determinate (has a defined number of elements) or indeterminate (has an undefined number of elements). To define a determinate array variable, specify the EXTENT option with the constant argument. This optional argument is an integer value that represents the number of data elements in the array variable. To define an indeterminate array variable, specify the EXTENT option without the constant argument.

The EXTENT is part of the variable data type. For more information, see the Type-name syntax reference entry.

An indeterminate array variable can be in one of two states: fixed or unfixed, meaning it either has a fixed dimension or it does not. An indeterminate array variable has an unfixed dimension when first defined. You can fix the dimension of an indeterminate array variable by:

• Initializing the array values when you define the variable, using the INITIAL option
• Setting the number of elements in the array variable using the EXTENT statement
• Assigning a determinate array to the indeterminate array, fixing it to the dimension of the determinate array
• Passing array parameters to a procedure, user-defined function, or class-based method, so that the indeterminate array variable is the target for the passing of a determinate array, fixing the indeterminate array to the dimension of the determinate array

Once fixed, ABL treats a fixed indeterminate array as a determinate array.

If you want to define a variable that is like an array variable or field, using the LIKE option, but you do not want the variable to be an array, you can use EXTENT 0 to indicate a non-array field.

If you are using the AS option and you do not use the EXTENT option (or you specify constant as 0), the variable is not an array variable. If you are using the LIKE field option and you do not use the EXTENT option, the variable uses the extent defined for the database field you name (if any).

SERIALIZE-NAME serialize-name

An optional CHARACTER constant that specifies the name of the variable as it should appear when serialized into JSON. The default is variable-name. Use this option when the serialized name contains invalid characters for an ABL name, is an ABL keyword, or an invalid JSON property name.

This option is only valid for class members, and it cannot be used if the variable is defined as NON-SERIALIZABLE or the class that contains it is not defined as SERIALIZABLE.

BGCOLOR expression

Specifies a background color for the variable in graphical interfaces. This option is ignored in character interfaces.

[ NOT ] CASE-SENSITIVE

CASE-SENSITIVE indicates that the value stored for a character variable is case sensitive, and that all comparisons operations involving the variable are case sensitive. If you do not use this option, ABL comparisons are usually case insensitive. If you define a variable LIKE another field of variable, the new variable inherits case sensitivity. Use [NOT] CASE-SENSITIVE to override this default.

COLUMN-LABEL label

Names the label you want to display above the variable data in a frame that uses column labels. If you want the label to use more than one line (a stacked label), use an exclamation point (!) in the label to indicate where to break the line. For example:

r-collbl.p

DEFINE VARIABLE credit-percent AS INTEGER NO-UNDO   COLUMN-LABEL "Enter   !percentage!increase ". FOR EACH Customer:   DISPLAY Customer.Name Customer.CreditLimit.   SET credit-percent.   Customer.CreditLimit = (Customer.CreditLimit *     (credit-percent / 100)) + Customer.CreditLimit.   DISPLAY Customer.CreditLimit @ new-credit LIKE Customer.CreditLimit     LABEL "New max cred". END.

If you want to use the exclamation point (!) as one of the characters in a column label, use two exclamation points (!!).

The AVM does not display column labels if you use the SIDE-LABELS or NO-LABELS options with the Frame phrase.

If you define a variable to be LIKE a field, and that field has a column label in the Data Dictionary, the variable inherits that column label.

CONTEXT-HELP-ID expression

An integer value that specifies the identifier of the help topic for this variable in a help file specified at the session, window or dialog box level using the CONTEXT-HELP-FILE attribute.

DCOLOR expression

Specifies the display color for the variable in character interfaces. This option is ignored in graphical interfaces.

DECIMALS  n

Specifies the number of decimal places to store for a DECIMAL variable, where n is an integer constant. When you define a variable AS DECIMAL, ABL automatically stores up to 10 decimal places for the value of that variable. Use the DECIMALS option to store a smaller number of decimal places. The DECIMALS option has nothing to do with the display format of the variable, just the storage format.

If you use the LIKE option to name a field whose definition you want to use to define a variable, ABL uses the number of decimals in the field definition to determine how many decimal places to store for the variable.

Note: The XML-WRITE() method on a temp-table, temp-table buffer, or ProDataSet object also uses the DECIMALS attribute to determine the number of decimal places to export to the XML Document.

DROP-TARGET

Indicates whether you want to be able to drop a file onto the object.

The following example shows setting the DROP-TARGET option for a variable:

DEFINE VARIABLE fill-in-1 AS CHARACTER DROP-TARGET.

FGCOLOR expression

Specifies a foreground color for the variable in graphical interfaces. This option is ignored in character interfaces.

FONT expression

Specifies a font for the variable.

FORMAT string

The data format of the variable you define. If you use the AS primitive-type-name option and you do not use FORMAT string, the variable uses the default format for its data type. The following table lists the default data formats for the data types.

Default display formats

Data type	Default display format
BLOB1	See footnote 1.
CHARACTER	x(8)
CLASS2	N/A
CLOB1	See footnote 1.
COM-HANDLE	>>>>>>9
DATE	99/99/99
DATETIME	99/99/9999 HH:MM:SS.SSS
DATETIME-TZ	99/99/9999 HH:MM:SS.SSS+HH:MM
DECIMAL	->>,>>9.99
HANDLE	>>>>>>9
INT64	->,>>>,>>9
INTEGER	->,>>>,>>9
LOGICAL	yes/no
LONGCHAR1	See footnote 1.
MEMPTR1	See footnote 1.
RAW1	See footnote 1.
RECID	>>>>>>9
ROWID1	See footnote 1.

See OpenEdge Getting Started: ABL Essentials for more information on data formatting.

If you use the LIKE field option and you do not use the FORMAT string option, the variable uses the format defined for the database field you name. You must enclose the string in quotes.

INITIAL {constant| [ constant[ , constant] . . . ] }

The initial value of the variable you want to define. If you use the AS primitive-type-name option and you do not use the INITIAL constant option, the default is the initial value for the data type of the variable or array element.

When you define an array variable, you can supply initial values for each element in the array. For example:

DEFINE VARIABLE array-var AS CHARACTER NO-UNDO EXTENT 3   INITIAL ["Add","Delete","Update"].

If you do not supply enough values to fill up the elements of the array, the AVM puts the last value you named into the remaining elements of the array. If you supply too many values, the AVM raises an error.

If you define a variable as an indeterminate array, and you supply initial values for elements in the array, the AVM fixes the number of elements in the array and treats the fixed indeterminate array as a determinate array. For example, the arrays defined by the following statements are equivalent:

DEFINE VARIABLE x  AS INTEGER NO-UNDO EXTENT   INITIAL [1,2,3]. DEFINE VARIABLE x1 AS INTEGER NO-UNDO EXTENT 3 INITIAL [1,2,3].

You can also use the EXTENT statement to fix the number of elements in an unfixed indeterminate array variable. For more information, see the EXTENT statement reference entry.

The following table lists the default initial values for the various variable data types.

Default variable initial values

Data type	Default initial value
CHARACTER	"" (an empty string)
CLASS3, 4	Unknown value (?)
COM-HANDLE4	Unknown value (?)
DATE	Unknown value (?) (displays as blanks)
DATETIME	Unknown value (?)
DATETIME-TZ	Unknown value (?)
DECIMAL	0
HANDLE4	Unknown value (?)
INT64	0
INTEGER	0
LOGICAL	no
LONGCHAR	Unknown value (?)
MEMPTR4	A zero-length sequence of bytes
RAW4	A zero-length sequence of bytes
RECID	Unknown value (?)
ROWID4	Unknown value (?)

If you are using the LIKE field option and you do not use the INITIAL constant option, the variable uses the initial value of the field or variable. In the DEFINE SHARED VARIABLE statement, the INITIAL option has no effect. However, the DEFINE NEW SHARED VARIABLE, the DEFINE NEW SHARED TEMP-TABLE, and the DEFINE NEW WORK-TABLE statements work with the INITIAL option.

LABEL string[ , string]...

The label you want to use when the variable is displayed. If you use the AS primitive-type-name option and you do not use the LABEL string option, the default label is the variable name. If you use the LIKE field option and you do not use the LABEL string option, the variable uses the label of the field or variable you name. You must enclose the string in quotes.

You can specify a label for each element in a determinate array variable. You cannot specify a label for elements in an indeterminate array variable.

In MS-Windows, you can designate a character within each label as a navigation mnemonic. Precede the character with an ampersand (&). When the variable is displayed with side labels, the mnemonic is underlined. The user can move focus to the variable by pressing ALT and the underlined letter. Navigation mnemonics operate only when you use side labels. If you specify more than one widget with the same mnemonic, the AVM transfers focus to each of these in tab order when you make a selection.

Ending a label with an ampersand might produce unwanted behavior. To include a literal ampersand within a label, specify a double ampersand (&&).

MOUSE-POINTER expression

Specifies the default mouse pointer for the variable.

NO-UNDO

When the value of a variable is changed during a transaction and the transaction is undone, the AVM restores the value of the variable to its prior value. If you do not want, or if you do not need, the value of a variable to be undone even when it has been changed during a transaction, use the NO-UNDO option with the DEFINE VARIABLE statement. NO-UNDO variables are more efficient; use this option whenever possible.

Specifying NO-UNDO for a variable is especially useful if you want to indicate an error condition as the value of the variable, perform an UNDO, and later take some action based on that error condition. If one variable is defined LIKE another that is NO-UNDO, the second variable will be NO-UNDO only if you specify NO-UNDO in the definition of the second variable.

PFCOLOR expression

Specifies the prompt-for color for the variable in character interfaces. This option is ignored in graphical interfaces.

view-as-phrase

Specifies the default data representation widget for this variable. Following is the syntax for the view-as-phrase:

VIEW-AS   {     combo-box-phrase      |  editor-phrase      |  FILL-IN           [ NATIVE ]           [size-phrase]           [ TOOLTIP tooltip]      |  radio-set-phrase      |  selection-list-phrase      |  slider-phrase      |  TEXT           [size-phrase]           [ TOOLTIP tooltip]      |  TOGGLE-BOX           [size-phrase]           [ TOOLTIP tooltip]   }

For more information on view-as-phrase, see the VIEW-AS phrase reference entry.

trigger-phrase

Defines triggers for the data representation widget specified in the view-as-phrase. Following is the syntax for the trigger-phrase:

TRIGGERS:   { ON event-list[ ANYWHERE ]       {     trigger-block          |  PERSISTENT RUN proc-name               [ IN handle]               [ ( input-parameters ) ]       }   }... END [ TRIGGERS ]

For more information on triggers, see the Trigger phrase reference entry.

Example

The r-dfvar.p procedure defines two variables, del and nrecs to be shared with procedure r-dfvar2.p. The del variable passes information to r-dfvar2.p, while nrecs passes information back to r-dfvar.p from r-dfvar2.p.

r-dfvar.p

DEFINE NEW SHARED VARIABLE del   AS LOGICAL NO-UNDO.
DEFINE NEW SHARED VARIABLE nrecs AS INTEGER NO-UNDO.

MESSAGE "Do you want to delete the orders being printed (y/n)?" UPDATE del.
RUN r-dfvar2.p.
IF del THEN
  MESSAGE nrecs "orders have been shipped and were deleted".
ELSE 
  MESSAGE nrecs "orders have been shipped".

r-dfvar2.p

DEFINE SHARED VARIABLE del   AS LOGICAL NO-UNDO.
DEFINE SHARED VARIABLE nrecs AS INTEGER NO-UNDO.

OUTPUT TO PRINTER.
FOR EACH Order WHERE Order.ShipDate <> ?:
   nrecs = nrecs + 1.
   FOR EACH OrderLine OF Order:
     DISPLAY OrderLine.OrderNum OrderLine.LineNum OrderLine.Qty
       OrderLine.Price.
       IF del THEN DELETE OrderLine.
   END.
   IF del THEN DELETE Order.
END.
OUTPUT CLOSE.

The following example is a startup procedure. It defines a new global variable with the initial value TRUE and uses that variable to determine whether to run an initialization procedure, r-init.p, that displays sign-on messages. Then the global variable first-time is set to FALSE. If you restart this procedure during the same session (pressed STOP), r-init.p does not run again.

The procedure also defines the variable selection for entering menu choices within this procedure:

r-dfvar3.p

DEFINE NEW GLOBAL SHARED VARIABLE first-time AS LOGICAL NO-UNDO INITIAL TRUE.
DEFINE VARIABLE selection AS INTEGER NO-UNDO FORMAT "9" LABEL "Selection".

IF first-time THEN DO:
  RUN r-init.p.
  first-time = FALSE.
END.

FORM
  "    MAIN MENU          " SKIP(1)
  "1 - Accounts Payable   " SKIP
  "2 - Accounts Receivable" 
  WITH CENTERED ROW 5 FRAME menu.

REPEAT:
  VIEW FRAME menu.
  UPDATE selection AUTO-RETURN WITH FRAME sel CENTERED ROW 12 SIDE-LABELS.
  IF selection = 1 THEN DO:
    HIDE FRAME menu.
    HIDE FRAME sel.
    RUN apmenu.p.
  END.
  ELSE IF selection = 2 THEN DO:
    HIDE FRAME menu.
    HIDE FRAME sel.
    RUN armenu.p.
  END.
  ELSE DO:
    MESSAGE "Invalid selection. Try again".
    UNDO, RETRY.
  END.
END.

The following procedure finds the day of the week of a date the user enters. The procedure defines an array with seven elements and uses the INITIAL option to define the initial value of each element in the array.

r-dfvar4.p

DEFINE VARIABLE dow AS CHARACTER NO-UNDO FORMAT "x(9)" EXTENT 7
  INITIAL ["Sunday", "Monday", "Tuesday", "Wednesday",
  "Thursday", "Friday", "Saturday"].

DEFINE VARIABLE dob AS DATE NO-UNDO INITIAL TODAY.

REPEAT WITH SIDE-LABELS 1 DOWN CENTERED ROW 10 TITLE "Date of Birth":
  DISPLAY SKIP(1).
  UPDATE dob LABEL "Enter date of birth".
  DISPLAY dow[WEEKDAY(dob)] LABEL "It was a".
END.

The following example defines a variable with a VIEW-AS phrase and a Trigger phrase:

r-defsel.p

DEFINE VARIABLE ix    AS INTEGER   NO-UNDO.
DEFINE VARIABLE clubs AS CHARACTER NO-UNDO
  VIEW-AS SELECTION-LIST SIZE 20 BY 5 MULTIPLE SCROLLBAR-VERTICAL NO-DRAG
    LIST-ITEMS "One Iron", "Two Iron", "Three Iron", "Four Iron",
               "Five Iron", "Six Iron", "Seven Iron", "Eight Iron",
               "Nine Iron", "Pitching Wedge"
  LABEL "Golf Clubs Available"
  TRIGGERS:
    ON GO DO:
      IF SELF:SCREEN-VALUE <> "" THEN
      DO ix = 1 TO NUM-ENTRIES(SELF:SCREEN-VALUE) :
        DISPLAY ENTRY(ix, SELF:SCREEN-VALUE) FORMAT "X(16)" 
          WITH FRAME clubs-sel CENTERED 
            NUM-ENTRIES(SELF:SCREEN-VALUE) + 1 DOWN
            TITLE "Clubs Selected" USE-TEXT.
        DOWN 1 WITH FRAME clubs-sel. 
      END.
    END.
  END TRIGGERS.
    
ENABLE clubs WITH FRAME get-info TITLE "Select the Desired Club(s)".
WAIT-FOR WINDOW-CLOSE OF CURRENT-WINDOW.

For examples of instance and static variable data member definitions, see the descriptions of r-CustObj.cls, r-CustObjStatic.cls, and r-CustObjAbstract.cls in the CLASS statement reference entry.

Notes

• You can use the DEFINE VARIABLE statement anywhere. However, all references to the variable must appear after the DEFINE VARIABLE statement that defines it.
• You cannot define a variable as a BLOB or CLOB field. You can define a variable using their MEMPTR and LONGCHAR counterparts, respectively.
• A HANDLE variable defined as a static data member can reference the handle of any compile-time defined (static) or run-time defined (dynamic) handle-based object, such as a button, temp-table, or ProDataSet.
• Defining a LONGCHAR variable supports the same options as a CHARACTER variable, except for the FORMAT option and all VIEW-AS options except VIEW-AS EDITOR LARGE.
• You should use the CASE-SENSITIVE option only when it is important to distinguish between uppercase and lowercase values entered for a character variable. For example, use CASE-SENSITIVE to define a variable for a part number that contains mixed uppercase and lowercase characters.
• After you use the DEFINE NEW GLOBAL SHARED VARIABLE statement to create a global shared variable, use the DEFINE SHARED VARIABLE statements in other procedures to access that variable.
• You cannot define the same global variable twice in the same ABL session. If you try, and the definitions of the two variables do not match, the AVM raises an error. If the definitions of the two variables match, the AVM disregards the second variable you tried to define (if you are rerunning a startup procedure).
• Changes made to variables when there is no active transaction are not undone when a block is undone.
• When a procedure names and uses a shared variable:
  • The AVM searches through the calling chain of procedures looking for the most recent DEFINE NEW SHARED VARIABLE statement that created that shared variable.
  • If no DEFINE NEW SHARED VARIABLE statement is found, the AVM searches for a DEFINE NEW GLOBAL SHARED VARIABLE statement that created the shared variable.
  • If the procedure that names the shared variable is called from a trigger or internal procedure that is part of a persistent procedure context, the persistent context is also checked for the most recent DEFINE NEW SHARED VARIABLE or DEFINE NEW GLOBAL SHARED VARIABLE statement at the point in the calling chain where the trigger or internal procedure is executed.
  • If the AVM finds one of these statements, it does not search any further for other statements that might have defined the same variable as NEW or NEW GLOBAL.
• The AVM checks the definition of a SHARED variable against that of the corresponding NEW SHARED or NEW GLOBAL SHARED variable. The data types and array extents must match. If the FORMAT, LABEL and DECIMALS specifications are not the same, each procedure uses its individual specification. The DEFINE NEW SHARED statement determines if a shared variable is NO-UNDO.
• A SHARED variable remains in scope for an instance of a persistent procedure until the instance is deleted. This is true even if the original procedure that defined the variable as NEW SHARED goes out of scope while the procedure instance remains persistent.

  If a trigger or internal procedure of a persistent procedure executes an external subprocedure that defines a SHARED variable, the AVM includes the persistent procedure in the resolution of the corresponding NEW SHARED variable as though the procedure were on the procedure call stack.

• If an application with several procedures defines a NEW SHARED variable with the same name in each procedure, the AVM creates a different instance of the NEW SHARED variable in each procedure. This behavior supports recursive procedures and bill-of-materials applications.
• You can neither define a SHARED or NEW SHARED variable, nor access such a variable defined in a procedure file, from within a class definition (.cls) file. If you do, ABL generates a compilation error. However, multiple procedure (.p) files can define and access an object reference variable for a class instance as a NEW SHARED or NEW GLOBAL SHARED variable. In this case, the object reference variables must be defined for the same class (not a subclass or a super class) in all procedures that use them.
• For SpeedScript, the following options are invalid: BGCOLOR, CONTEXT-HELP-ID, DCOLOR, FONT, FGCOLOR, MOUSE-POINTER, PFCOLOR, and view-as-phrase.

See also

Class-based data member access, DEFINE BUFFER statement, RUN statement, Trigger phrase, Type-name syntax, USING statement, VIEW-AS phrase