Closed
Description
Use Case
When a json string has a null value, parsing a struct with optional fields fails.
I would expect { "foo": null, "bar": "bar" } to parse into the struct:
Foo {
foo: nil
bar: "bar"
}Example of failure:
let json = "\{\"foo\": null, \"bar\": \"bar\"}";
struct Foo {
foo: str?;
bar: str?;
}
Foo.parseJson(json);Error: unable to parse Foo:
- Foo/foo must be string
--> wing/main.w:6:1
| foo: str?;
| }
|
6 | Foo.parseJson(json);
| ^
at /app/wing/main.w:6:1
I get why this is happening in wing, but null keys in json are pretty common and this makes parsing directly to structs pretty unsafe.
Proposed Solution
If the field is optional, it should be set to nil.
i.e. {"foo": null} should give parse into the struct when foo is optional:
Foo {
foo: nil
}Implementation Notes
No response
Component
No response
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