Merge pull request #531 from ProvableHQ/IGI-111/empty-loops

Update for loop docs

Author: IGI-111

documentation/language/05_control_flow.md

@@ -46,8 +46,10 @@ Return statements are declared as `return {expression};`.
 
 ### For Loops
 
-For loops are declared as `for {variable: type} in {lower bound}..{upper bound}`. The loop bounds must be integer constants of the same type. Furthermore, the lower bound must be
-less than the upper bound. Nested loops are supported.
+For loops are declared as `for {variable: type} in {lower bound}..{upper bound}`.
+The loop bounds must be integer constants of the same type. Furthermore, if
+the lower bound is superior or equal to the upper bound, the loop will result in no operations.
+Nested loops are supported.
 
 
 ```leo