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|  | **#LOOP** [, | | **UNTIL(** //expression// **)** | ] |
|  |  | | **WHILE(** //expression// **)** | |
|  |  | | **FOR(** //counter, start, end// **)** [, **BY(** //step// **)** ] | |
|  |  | | **TIMES(** //iterations// **)** | |
|  | //statements// |  |
|  | **#ENDLOOP** |  |

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| **#LOOP** | Initiates an iterative statement execution structure. |
| **UNTIL** | Evaluates its //expression// before each iteration of the #LOOP. If its //expression// evaluates to true, the #LOOP control sequence terminates. |
| //expression// | Any Template language expression which can evaluate to false (blank or zero) or true (any other value). |
| **WHILE** | Evaluates its //expression// before each iteration of the #LOOP. If its //expression// evaluates to false, the #LOOP control sequence terminates. |
| **FOR** | Initializes its //counter// to the //start// value, and increments it by the //step// value each time through the loop. When the //counter// is greater than the //end// value, the #LOOP control sequence terminates. |
| //counter// | A user-defined symbol used as the loop counter. |
| //start// | An expression containing the initial value to which to set the loop //counter//. |
| //end// | An expression containing the ending value of the loop //counter//. |
| **BY** | Explicitly defines the increment value for the //counter//. |
| //step// | An expression containing the increment value for the //counter//. If omitted, the //step// defaults to one (1). |
| **TIMES** | Loops the number of times specified by the //iterations//. |
| //iterations// | An expression containing the number of times to loop. |
| //statements// | One or more target and/or Template Language statements. |
| **#ENDLOOP** | Terminates the #LOOP structure. |

A **#LOOP** structure repetitively executes the //statements// within its structure. The #LOOP structure must be terminated by **#ENDLOOP**. If there is no #ENDLOOP, an error message is issued during Template file pre-processing. A #LOOP structure may be nested within another #LOOP structure.

The **#LOOP,UNTIL** or **#LOOP,WHILE** statements create exit conditions for the #LOOP. Their //expressions// are always evaluated at the top of the #LOOP, before the #LOOP is executed. A #LOOP WHILE structure continuously loops as long as the //expression// is true. A #LOOP UNTIL structure continuously loops as long as the //expression// is false. The //expression// may contain Template symbols, constant values, and any of the arithmetic, Boolean, and logical operators documented in the //Language Reference//. Procedure calls are allowed. If the modulus division operator (%) is used in the //expression//, it must be followed by at least one blank space (to explicitly differentiate it from the Template symbols).

The **#LOOP,FOR** statement also creates an exit condition for the #LOOP. The #LOOP initializes the //counter// to the //start// value on its first iteration. The #LOOP automatically increments the //counter// by the //step// value on each subsequent iteration, then evaluates the //counter// against the //end// value. When the //counter// is greater than the //end//, the #LOOP control sequence terminates.

#LOOP (without WHILE, UNTIL, or FOR) loops continuously, unless a #BREAK or #RETURN statement is executed. #BREAK terminates the #LOOP and continues execution with the statement following the #LOOP structure. All //statements// within a #LOOP structure are executed unless a #CYCLE statement is executed. #CYCLE immediately gives control back to the top of the #LOOP for the next iteration, without executing any statements following the #CYCLE in the #LOOP.

**Example:**

**#SET(%LoopBreakFlag,'NO')**

**#LOOP****                                #!Continuous loop**

**  #INSERT(%SomeRepeatedCodeGroup)**

**  #IF(%LoopBreakFlag = 'YES')        #!Check break condition**

**    #BREAK**

**  #ENDIF**

**#ENDLOOP**

**#SET(%LoopBreakFlag,'NO')**

**#LOOP****,UNTIL(%LoopBreakFlag = 'YES')  #!Loop until condition is true**

**  #INSERT(%SomeRepeatedCodeGroup)**

**#ENDLOOP**

**#SET(%LoopBreakFlag,'NO')**

**#LOOP****,WHILE(%LoopBreakFlag = 'NO')   #!Loop while condition is true**

**  #INSERT(%SomeRepeatedCodeGroup)**

**#ENDLOOP**

**See Also:     **[[ break  break out of a loop .htm|#BREAK]] ,[[ cycle  cycle to top of loop .htm|#CYCLE]]