Add example for the function operator

[DesignThinkerer]

This PR add an example showing how to use the function operator to examine changes made on shadow tiddlers.

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[github-actions]

@DesignThinkerer It appears that this is your first contribution to the project, welcome.

With apologies for the bureaucracy, please could you prepare a separate PR to the 'tiddlywiki-com' branch with your signature for the Contributor License Agreement (see contributing.md).

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[pmario]

Filter operators have a system to link to examples. IMO we should keep that mechanism, for consistency reasons. See eg: https://deploy-preview-8793--tiddlywiki-previews.netlify.app/#all%20Operator

[DesignThinkerer]

Filter operators have a system to link to examples. IMO we should keep that mechanism, for consistency reasons.

I'm aware, however I was not able to find a way to elegantly display the predefined functions as seen in this tiddler:

https://deploy-preview-8793--tiddlywiki-previews.netlify.app/#filter%20Operator%20(Examples)

I used the same setup as usual, but with the new test case widget to allow the user to clearly see the functions that are being set. Here's an attempt anyway:

Which one do you prefer, with testcase or without testcase ?

[pmario]

Which one do you prefer, with testcase or without testcase ?

For consistency I personally prefer the "usual setup" as in the screenshot.

@Jermolene -- What do you think?

[kookma]

Thank you for examples.
I may propose simpler examples, I mean for pedagogical purposes, it is better to choose example have less or no other concept except the one you discuss here function.
The above examples have several advanced concepts: shadow tiddlers, startup, ...

One simple example is to list first five tiddlers tagged Learning. The number of results can be sent as an input attribute.

[DesignThinkerer]

Thank you for examples. I may propose simpler examples, I mean for pedagogical purposes, it is better to choose example have less or no other concept except the one you discuss here function

Ok, I added a function with the sole purpose of getting the value for a field, this way the complexity increase more gradually. I also used the format recommanded by @pmario.

I added an example at the end showing how these functions can be used together.

What do you think?

https://deploy-preview-8793--tiddlywiki-previews.netlify.app/#function%20Operator%20(Examples)

[kookma]

What do you think?

Much better, thank you!

[github-actions]

DesignThinkerer has signed the Contributor License Agreement (see contributing.md)

[Jermolene]

Thanks @DesignThinkerer