ProvideX V8.20 > Language Reference > 2. Directives
135
Format 2: For Loop, Simplified Syntax
FOR var ..NEXT [var]
This format executes the logic immediately following the FOR by the number of times
specified in the numeric value var; therefore, FOR 1 will execute the loop once, and
FOR 5 will execute the loop 5 times. A value of zero causes the loop to be skipped. An
error is generated if the numeric value is not an integer or it is less than zero.
If var is a simple numeric variable, the system will first set var to 1, then increment
up to its initial value. When var = 5, the loop will execute 5 times, with var starting at
1 and incrementing by 1 through each iteration to 5. At the completion of the loop,
var will equal its initial value. Regardless of whether a simple numeric variable is
used, TCB(19) will contain the current iteration count during the loop.
Example 1:
N = LEN(X$)
FOR N
IF X$(N,1) = "X" THEN X$(N,1) = "Y"
NEXT
Example 2:
TOT = 0
FOR DIM(READ MAX(Balance))
TOT += Balance[TCB(19)]
NEXT
Should a loop using a defined variable be prematurely exited (via BREAK, POP, or
EXITTO), the variable will remain at its last value; e.g.,
N = 10
FOR N
IF X$[N] = "" BREAK
...
NEXT
When the IF condition is satisfied and the FOR loop is exited via the BREAK, the
value in N will be the index into the array.
See Also
Loop Structures, User's Guide.