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//new declaration //**LIKE(**//like declaration//**) **[,**DIM( )**] [,**OVER( )**] [,**PRE( )**] [,**NAME( )**] [,**EXTERNAL**]

[,**DLL**][,**STATIC**] [,**THREAD**] [,**BINDABLE**]

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| **LIKE** | Declares a variable whose data type is inherited from another variable. |
| //new declaration// | The label of the new data element declaration. |
| //like declaration// | The label of the data element declaration whose definition will be used. This may be any simple data type, or a reference to any simple data type (except &STRING), or the label of a GROUP or QUEUE structure. |
| **DIM** | Dimension the variables into an array. |
| **OVER** | Share a memory location with another variable or structure. |
| **PRE** | Declare a label prefix for variables within the //new declaration// structure (if the //like declaration// is a complex data structure). This is not required, since you may use the //new declaration// in the Field Qualification syntax to directly reference any member of the new structure. |
| **NAME** | Specify an alternate, "external" name for the field. |
| **EXTERNAL** | Specify the variable is defined, and its memory is allocated, in an external library. Not valid within FILE, QUEUE, or GROUP declarations. |
| **DLL** | Specify the variable is defined in a .DLL. This is required in addition to the EXTERNAL attribute. |
| **STATIC** | Specify the variable's memory is permanently allocated. |
| **THREAD** | Specify memory for the variable is allocated once for each execution thread. Also implicitly adds the STATIC attribute on Procedure Local data. |
| **BINDABLE** | Specify all variables in the group may be used in dynamic expressions. |

**LIKE** tells the compiler to define the //new declaration// using the same definition as the //like declaration//, including all attributes. If the original //like declaration// changes, so does the //new declaration//.

The //new declaration// may use the DIM and OVER attributes. If the //like declaration// has a DIM attribute, the //new declaration// is already an array. If a further DIM attribute is added to the //new declaration//, the array is further dimensioned.

The PRE and NAME attributes may be used, if appropriate. If the //like declaration// already has these attributes, the //new declaration// will inherit them and compiler errors can occur. To correct this, specify a PRE or NAME attribute on the //new declaration// to override the inherited attribute.

If the //like declaration// names a QUEUE, LIKE does not create a new QUEUE, because the //like declaration// is simply treated as a GROUP. The //like declaration// QUEUE is converted to a //new declaration// GROUP. The same is true if the //like declaration// is a RECORD structure. Similarly, if the //like declaration// is a MEMO, the //new declaration// becomes a STRING of the maximum size of the MEMO.

You may use LIKE to create a new instance of a CLASS. However, simply declaring the new instance by naming the CLASS as the data type performs an implicit LIKE. For either type of instance declaration, the DIM, OVER, PRE, and NAME attributes are invalid; all other attributes are valid for a CLASS instance declaration.

**Example:**

**Amount       REAL                 !Define a field**

**QTDAmount    LIKE(Amount)         !Use same definition**

**YTDAmount    LIKE(QTDAmount)      !Use same definition again**

**MonthlyAmts  LIKE(Amount),DIM(12) !Use same definition for array, 12 elements**

**AmtPrPerson  LIKE(MonthlyAmts),DIM(10)**

**             !Use same definition for array of 120 elements (12,10)**

**Construct GROUP                   !Define a group**

**Field1     LIKE(Amount)           ! Construct.field1 - real**

**Field2     STRING(10)             ! Construct.field2 - string(10)**

**          END**

**NewGroup  LIKE(Construct)        !Define new group, containing **

**                                 ! NewGroup.field1 - real**

**                                 ! NewGroup.field2 - string(10)**

**MyQue    QUEUE                   !Define a queue**

**Field1     STRING(10)**

**Field2     STRING(10)**

**         END**

**MyGroup  LIKE(MyQue)             !Define new GROUP, like the QUEUE**

**AmountFile FILE,DRIVER('Clarion'),PRE(Amt)**

**Record      RECORD**

**Amount       REAL          !Define a field**

**QTDAmount    LIKE(Amount)  !Use same definition**

**            END**

**           END**

**Animal    CLASS**

**Feed        PROCEDURE(short amount),VIRTUAL**

**Die         PROCEDURE**

**Age         LONG**

**Weight      LONG**

**          END**

**Cat       LIKE(Animal) !New instance of an Animal CLASS**

**Bird      Animal       !New instance of an Animal CLASS (implicit LIKE)**

**See Also:**

[[dim  set array dimensions .htm|DIM]]

[[over  set shared memory location .htm|OVER]]

[[pre  set label prefix .htm|PRE]]

[[name  set external name .htm|NAME]]

[[field qualification.htm|Field Qualification]]