Question regarding the analysis phase and the `rec...

# pattern-matching

[mattmoore]

Question regarding the analysis phase and the record function from the bindingcontext: Would record end up creating a new node? Also wondering how I would delete/replace nodes from here? Or would the analysis phase be used mainly for suppressing the IntelliJ errors?

[raulraja]

record will assign to the Kt expression _ or any other a type which currently is null right before analysis completes and it will let you get through to IR codegen

[mattmoore]

Would I just be assigning an existing kotlin type? Or create a new type to represent _? I guess what I'm trying to say is would I rewrite the offending node _ during this time or just assign it a type and rewrite after analysis for IR codegen?

[mattmoore]

For example (may be wrong!):

Analysis
   |
   v
Change _ to valid type
   |
   v
Desugar _ to something valid prior to IR codegen
   |
   v
IR Codegen

vs:

Analysis
   |
   v
Change _ to valid type
   |
   v
IR Codegen
   |
   v
Desugar _ to something valid during IR codegen (IR transformation?)

[mattmoore]

I think the latter is the correct answer. After looking at https://github.com/arrow-kt/arrow-meta/blob/master/compiler-plugin/src/main/kotlin/arrow/meta/dsl/codegen/ir/IrSyntax.kt I think I'm understanding more. So yes, analysis is just to get intellij to behave, then I can apply tree transform in the IR codegen phase using the functions in IrSyntax

[mattmoore]

Sorry, still wrapping my head around how the phases relate to each other. 😬

[raulraja]

no worries, that makes sense

[raulraja]

you would be obtaining the type from the Person constructor first arg and using that type on record

[raulraja]

that will record _ as String

[raulraja]

then in codegen you will replace those

[mattmoore]

Ah thanks!. OK. I guess I'm getting this after all 🙂 I'm hoping to try that out tonight or tomorrow.