We got an idea for FileMaker. The macOS NSView class allows an application developer to register a function to provide a tooltip on demand. Instead of filling tooltips earlier, you can later decide on the value and generate it on the fly.
To implement tooltips, we register for providing tooltips. When you move mouse over the text lines, the plugin is called and asked for the tooltip text. We then look on the mouse position and what text is below the mouse position. This text is scanned for a word to left and right. We look for double double colon "::" and for one or two $ signs. If we have a text starting with $ or text::text, we evaluate this and see if FileMaker can provide us a value. If we have a value, we show the content in the tooltip. This includes the data type, so you can distinguish a text containing a number from a pure number.
Please notice that we evaluate in current context, so we get current value, not a value from past. And we don't support field or variable names with spaces inside. There may be other characters we incorrectly recognize as being part or not part of an identifier. Let us know if you find a bug.
All our changes to FileMaker Pro move the experience more from low code to pro code category. We provide improvements for the power users to better work in FileMaker. Since we provide the features from outside, we are limited in various ways. For example FileMaker internally knows better about what variables or fields are used and could provide this more efficient. Of course we would enjoy if Claris implements a few of the features into the product. But for the time being, we are happy to help and encourage everyone to try our features. And for the case there will be problems with future versions, we provide a checkbox in preferences to disable the changes.
This feature will be available with next pre-release version of our plugin and is for macOS only. Seems to work fine from FileMaker 15 to the latest 19.x release. Please do not hesitate to contact us with questions.