tiny.preserves.assertIsDomain

1/// Stops compilation unless `D` declares public functions named `eql`, `order`, `deinit` and2/// `clone`. Code that writes a generic over `Value` calls it first, as `Value` and every generic of3/// the package do, so a type of embedded values that breaks the rules fails. The check tests that4/// the names exist and reads no signature. The error names the missing function and the signature5/// the package calls: `eql(a: Self, b: Self) bool`, `order(a: Self, b: Self) std.math.Order`,6/// `deinit(self: *Self, allocator: Allocator) void` and7/// `clone(self: Self, allocator: Allocator) !Self`.8pub fn assertIsDomain(comptime D: type) void {9    if (!@hasDecl(D, "eql")) {10        @compileError("Domain " ++ @typeName(D) ++ " is missing `pub fn eql(a: Self, b: Self) bool`");11    }12    if (!@hasDecl(D, "order")) {13        @compileError("Domain " ++ @typeName(D) ++ " is missing `pub fn order(a: Self, b: Self) std.math.Order`");14    }15    if (!@hasDecl(D, "deinit")) {16        @compileError("Domain " ++ @typeName(D) ++ " is missing `pub fn deinit(self: *Self, allocator: Allocator) void`");17    }18    if (!@hasDecl(D, "clone")) {19        @compileError("Domain " ++ @typeName(D) ++ " is missing `pub fn clone(self: Self, allocator: Allocator) !Self`");20    }21}

1pub const assertIsDomain = domain.assertIsDomain;