JSON, Level: Advanced, Version: FM 18 or later

FM18: JSON.UpdateArrayElement

Disclaimer: the technique shown in this article is an attempt to work around an annoyance that can crop up when using FileMaker’s native JSONSetElement function, and is provided on an as-is basis. Use with appropriate caution and at your own risk.

Acknowledgement: I owe a debt of gratitude to Paul Jansen for many illuminating JSON-related discussions over the last year or so. Thank you Paul.

Bug fixes: Demo file has been updated to v3.

Introduction

Today we’re going to look at a custom function, JSON.UpdateArrayElement, written to circumvent a problem you may encounter when using JSONSetElement. (Note: see Thinking About JSON, part 1 and part 2 if you need a basic FM/JSON overview or refresher.)

Demo file: JSON-UpdateArrayElement-v3.zip (requires FM 18 or later)

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Why did I write a custom function to do what JSONSetElement apparently already does? Because under certain circumstances JSONSetElement does not work the way I believe it should. We’ll get to the custom function in a minute, but first there are a couple issues we need to examine. Continue reading “FM18: JSON.UpdateArrayElement”

Level: Intermediate, Version: FM 18 or later

New in FM 18: While, part 2

Today we’re going to dig a little deeper into the new-in-18 While function, and to avoid repetition, will assume readers are familiar with last month’s article on SetRecursion and While. We’ll look at some new examples ranging from basic to advanced, investigate the circumstances under which While can use variables previously declared via Let, and check out some benchmark results comparing While vs. CustomList.

Demo Files

Continue reading “New in FM 18: While, part 2”

Level: Intermediate, Version: FM 18 or later

New in FM 18: SetRecursion and While

Author’s note: Inevitable comparisons will be drawn between the new While function and the venerable CustomList custom function, which I wrote about at length several years ago. Preliminary testing indicates that CustomList is faster under certain circumstances and While is faster under others. In my opinion, both of them belong in your developer tool kit.

Today we’re going to take a look at two new functions introduced in FileMaker 18: SetRecursion and While, and you can follow along in today’s demo files if you are so inclined.

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Demo files: While-Sandbox.zip and Maclaurin-Series.zip

Continue reading “New in FM 18: SetRecursion and While”