Implement lexical scoping with let expressions #307
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See jmespath/jmespath.jep#18 for more details.
| "comment": "Bindings only visible within expression clause", | ||
| "expression": "let $a = 'top-a' in let $a = 'in-a', $b = $a in $b", | ||
| "result": "top-a" |
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Any reason why we don't want the bindings to update as they are being processed/created ?
It could be useful to allow referencing a binding previously declared.
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This would enable mutually recursive definitions, analogous to letrec in other languages. I'd rather have user defined functions be the mechanism to define that, if that ever ends up happening.
BTW, the best place for questions related to the spec would be on the tracking proposal.
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If variables are set up in the same order they are declared would this be subject to recursive definition ?
I mean $a is assigned first, then $b comes after that and uses $a, etc...
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I see the comments on the tracking proposal linked, moving the discussion over there.
See jmespath/jmespath.jep#18 for more details.
NOTE: The JEP is still in the review stage, and is subject to change. This PR won't be merged until the JEP is finalized and approved. I'm sending the PR now in case anyone wants to try it out and experiment with the feature in order to give better feedback.
I'm still going to be testing this more thoroughly, there might be some bugs. I did add the testcases from the JEP as part of this change, and those tests (along with the existing compliance tests) are all passing.