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 for

loop command

 Syntax
 ```For I := N_1 To N_2 Do C EndFor For I := N_1 To N_2 Step D Do C EndFor where I is a dummy variable, N_1, N_2, and D are integer expressions, and C is a sequence of commands. ```

 Description
In the first form, the variable I is assigned the values N_1, N_1+1, ...,N_2 in succession. After each assignment, he command sequence C is executed. The second form is the same, except that I is assigned the values N_1, N_1+D, N_1+2D , and so on, until the limit N_2 is passed. If N_2 < N_1 , then the command sequence C is not executed.

NOTE: Large values for N_1, N_2 , or D are not permitted; typically they should lie in the range about -10^9 to +10^9.

 Example
 ```/**/ For N := 1 To 5 Do Print 2^N, " "; EndFor; 2 4 8 16 32 /**/ for n := 1 to 20 step 3 do print n, " "; endfor; 1 4 7 10 13 16 19 /**/ For N := 10 To 1 Step -2 Do Print N, " "; EndFor; 10 8 6 4 2 /**/ For N := 5 To 3 Do Print N, " "; endfor; -- no output ```
Loops can be nested.

 Example
 ```/**/ Define MySort(ref L) /**/ For I := 1 To len(L)-1 Do /**/ M := I; /**/ For J := I+1 To len(L) Do /**/ If L[J] < L[M] Then M := J; EndIf; /**/ EndFor; /**/ If M <> I Then /**/ C := L[M]; /**/ L[M] := L[I]; /**/ L[I] := C; /**/ EndIf; /**/ EndFor; /**/ EndDefine; /**/ M := [5,3,1,4,2]; /**/ MySort(ref M); /**/ M; [1, 2, 3, 4, 5] ```
(Note that ref L is used so that the function can change the value of the variable referenced by L. See ref .)