How It Works

The format of a while function is broken into four parts: initial variables, the condition, logic, and the results. The function repeats the logic section until the condition is false; that is how the function provides the ability to loop. In the example below the While function returns a list of numbers 1 through 5:

While (
    [
     count = 1;
     numberList = ""
    ];
    count < 6 ;
    [
     numberList = numberList & (count) & "¶";
     count = count + 1
    ];
numberList
)

The function returns:

1
2
3
4
5

Notes

• Initial variables are available throughout the loop of the function.

• You can define multiple initial variables by enclosing them in brackets, similar to how let functions work.

• Variables that need to retain information from each iteration must be defined in the initial variable section otherwise their values are empty in the next iteration.

• To prevent infinite loops the while function will return "?" after the number of iterations exceeds a limit.

• The default limit is 50,000 iterations. Use the new function, Set Recursion, to set a new limit to the number of iterations.

Conclusion

With the advent of the While function, development of FileMaker applications will become a simpler and quicker process, eliminating the need for one-off recursive functions. Download the demo file to try out the new function!

Contact us if you have any questions about the While function or need help implementing your FileMaker solution.