Create variables from element values or names.

[TobiasNx]

At the moment you can only create variables from explicitly assigning values to variable names by put_var or put_vars.

I suggest a to_var function:

to_var("sourceElement","variableName",variableValue:"key/value")

Perhaps the feature for element names is not needed.

[blackwinter]

variableValue:"key/value"

I don't understand this part. What would it do?

Perhaps the feature for element names is not needed.

And this isn't clear to me, either. What is the "feature for element names"?

[TobiasNx]

variableValue:"key/value"

I don't understand this part. What would it do?

element:

"a" : "b"

1. value:
   to_var("a","variableName",variableValue:"value")

Variable: $[variableName]="b"

2. key:
   to_var("a","variableName",variableValue:"key")

Variable: $[variableName]="a"

Perhaps the feature for element names is not needed.

And this isn't clear to me, either. What is the "feature for element names"?

I was referring to 2 and therefore questioned if we need the option variableValue: at all.

[blackwinter]

I see, thanks for the clarification.

I was referring to 2 and therefore questioned if we need the option variableValue: at all.

As this would be equivalent to put_var('variableName', 'a'), I don't think we should pursue it.

[blackwinter]

But we need to specify how to_var() should behave if the path (sourceElement) matches a non-string.

[blackwinter]

We've previously discussed a similar issue in oersi/oersi-etl#221. The proposed "field value interpolation" would also be able to satisfy the use case here, thus obviating the need for a new function.

lookup("Sublibrary-ISIL", "$<HO-ISIL>.tsv", "sep_char": "\t", delete: "true")

[TobiasNx]

But we need to specify how to_var() should behave if the path (sourceElement) matches a non-string.

This should only work with string-elements, and should be overwritten if already exists.

I am not sure, but perhaps some of the code could be reused in metafacture/metafacture-core#533