Provide a way to specify types for enums

[ajrudzitis]

I have a type which uses two bytes to specify a type, although all the currently allowed values fit into a single byte. Vest seems to try to use the smallest type possible, however, this does not match the format.

My current workaround is to add a value to the enum, for example:

    FORCE_U16 = 0x0100,

However, it would be useful if the Vest syntax allowed me to be explicit. I could not find if this feature existed based on the documentation.

[y1ca1]

This is indeed a very useful feature to add and we will add support for this soon. Stay tuned!

[y1ca1]

We recently added support for adding type suffixes for integer literals (e.g., 0x00u8, 512u16, etc.). Can you take a look at

vest/vest-dsl/test/src/enums.vest

Lines 34 to 58 in 19d1c9f

	a_typed_closed_enum = enum {
	X = 0u16,
	Y = 1,
	Z = 2,
	}
	a_typed_choose(@e: a_typed_closed_enum) = choose(@e) {
	X => u8,
	Y => u16,
	Z => u32,
	}
	a_typed_open_enum = enum {
	P = 0x00u32,
	Q = 0x01u32,
	R = 0x02u32,
	...
	}
	a_typed_choose_with_default(@e: a_typed_open_enum) = choose(@e) {
	P => u8,
	Q => u16,
	R => u32,
	_ => Tail,
	}

and see if that looks good to you?

[ajrudzitis]

Yes, this looks usable. I'll have to wait until we pull the latest version into our internal systems to try it.

Given a choice, I may have preferred a way to force all valid values for the enum to resolve to a specific type. In your first example, will Y and Z also be represented as 0u16 values?

[y1ca1]

Given a choice, I may have preferred a way to force all valid values for the enum to resolve to a specific type. In your first example, will Y and Z also be represented as 0u16 values?

Yes, users can either specify all enum discriminants with (the same) type suffixes or just specify one of them, in which case the DSL would fix the choice for all the rest.