Wrote this code type grade = {math: int; physics: int; chemistry: int} type student = {id: string; name: string; grade: grade} type school = {school_name: string; `class`: string; students: student list} When I do a dune build all it says is a “syntax error” on the backtick. File “mytypes/mytype…

As the compiler says, that is not valid syntax. Typically people change the name slightly to avoid clashing with a reserved keyword. Eg, you could use the name class_ or cls.

So there is no way to escape it?

Well, there is the ‘raw keywords’ feature: \#class OCaml 5.2.0 released But that is available only in OCaml 5.2.0+, is not really meant for this use case, and is a super obscure feature that will confuse everyone who reads the code. In short, it would be advisable to stick with the typical pattern…

Nice hallucination there by ChatGPT. :stuck_out_tongue:

why not just use class_name as the variable?

Please, bullshit not hallucinations. [image] abhishes: But the compiler still doesn’t like it There is a manual where you can easily check the accuracy of whatever syntactic bullshit or “information” LLMs are going to tell you about the OCaml language. In general if something comes out wrong…

Or precede/follow with an underscore, viz class_ or _class

Rather not precede, because e.g. _class value binding will disable the “unused” warning.

I don’t think there’s a meaningful difference between adding an underscore or “escaping” the keyword. In either case, you’re still writing something that’s not class in your source code. (And since record field names only exist in source code, there’s no time where it would get “unescaped.”) You mig…

As a side note, in case you need to print or to export a type record information to JSON (it is similar for TOML etc) you can still export with the actual class name with something like: type school = { school_name: string ; class_name: string [@key "class"] ; students: …

Creating a Record where field name is a reserved keyword

Learning

floyer November 10, 2024, 8:00am 6

Bing copilot seems to have the same hallucination.

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Creating a Record where field name is a reserved keyword

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