Keyable

Only the following types can be used as a key in a map or on an entity.

• null. If undefined is used as a key, it will be treated as null
• Integers. Note that not all numbers are supported. If a floating point number with a decimal point is used as a key, it will be rounded to the nearest integer closest to zero.
• Assets
• Booleans
• Categories
• Colors
• Entities
• Flags
• Keycodes
• Strings
• Symbols