Enum Serialisation

Huml.Net serialises enum values as quoted strings and deserialises them by name lookup. Round-trips are symmetric: the same name used during serialisation is accepted during deserialisation.

Default Behaviour

Without any attributes or naming policy, the C# member name is used as the HUML string value:

public enum LogLevel { Debug, Info, Warning, Error }

public class Config
{
    public LogLevel Level { get; set; }
}

string huml = HumlSerializer.Serialize(new Config { Level = LogLevel.Warning });
// %HUML v0.2.0
// Level: "Warning"

var config = HumlSerializer.Deserialize<Config>("""
    %HUML v0.2.0
    Level: "Warning"
    """);
// config.Level == LogLevel.Warning

Custom Member Names — HumlEnumValueAttribute

Apply [HumlEnumValue("name")] to a field to override the HUML string for that member:

using Huml.Net.Serialization;

public enum LogLevel
{
    [HumlEnumValue("debug")]   Debug,
    [HumlEnumValue("info")]    Info,
    [HumlEnumValue("warning")] Warning,
    [HumlEnumValue("error")]   Error,
}

string huml = HumlSerializer.Serialize(new Config { Level = LogLevel.Warning });
// Level: "warning"

Naming Policy Integration

When HumlOptions.PropertyNamingPolicy is set, the policy transforms enum member names the same way it transforms property names — unless [HumlEnumValue] is present (which always wins):

var options = new HumlOptions { PropertyNamingPolicy = HumlNamingPolicy.KebabCase };

public enum ConnectionState { Connected, Disconnected, ReconnectingNow }

// With KebabCase policy (and no [HumlEnumValue]):
// Connected       → "connected"
// Disconnected    → "disconnected"
// ReconnectingNow → "reconnecting-now"

Deserialisation Lookup

Deserialisation uses a case-sensitive lookup first, falling back to case-insensitive lookup if no case-sensitive match is found. HumlDeserializeException is thrown if no match is found at all.

Limitations

[Flags] enums are not supported for serialisation. A combined flags value has no single member name, so serialising one throws HumlSerializeException.
Undefined numeric values throw. Serialising an enum value that does not correspond to a defined member (for example (LogLevel)99) throws HumlSerializeException rather than emitting the raw number.

Nullable Enums

Nullable enum properties (LogLevel?) are fully supported. A HUML null scalar maps to null in C#; a string value is looked up normally.

public class Config { public LogLevel? Level { get; set; } }

var config = HumlSerializer.Deserialize<Config>("""
    %HUML v0.2.0
    Level: null
    """);
// config.Level == null