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TomFrost / Jexl

Javascript Expression Language: Powerful context-based expression parser and evaluator
MIT License
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how to map one array to another array? #99

Closed naivefun closed 2 years ago

naivefun commented 3 years ago

for example: [1,2,3] to [1,4,9]

or object array with different object property name? [{name: 'a'}] to [{Name: 'a'}]

something like projections here: https://jmespath.org/tutorial.html#projections

TomFrost commented 2 years ago

Sorry for the late response on this!

At the moment, dynamic creation of functions is not supported. This was actually a big topic of discussion a few years back, but we didn't get to an implementation that was bulletproof and upheld all of Jexl's security features, so it was iced.

What you CAN do, if you're able to predict the kinds of mappings you'll need, is write those as transforms instead. Then from inside the expression, simply pipe your value to the named transform.

I'm going to close this since it's not currently in the scope of the project, but I'm happy to review any PR or proposal that implements closures in a sane way.