Quick Reference

A concise reference for all syntax currently supported by the SDDL2 compiler.

Types

Integer Types

Type	Size	Signed	Endianness
Byte	1	No	N/A
Int8 / UInt8	1	Yes / No	N/A
Int16LE / Int16BE	2	Yes	Little / Big
UInt16LE / UInt16BE	2	No	Little / Big
Int32LE / Int32BE	4	Yes	Little / Big
UInt32LE / UInt32BE	4	No	Little / Big
Int64LE / Int64BE	8	Yes	Little / Big
UInt64LE / UInt64BE	8	No	Little / Big

Float Types (type descriptors only — cannot be used in expressions)

Type	Size	Endianness
Float16LE / Float16BE	2	Little / Big
Float32LE / Float32BE	4	Little / Big
Float64LE / Float64BE	8	Little / Big
BFloat16LE / BFloat16BE	2	Little / Big

Byte Sequences

Syntax	Description
Bytes(n)	Exactly n bytes as a serial field

Syntax Quick Reference

Records

Record Name() = { field: Type, ... }         # basic
Record Name(PARAM1, PARAM2) = { ... }        # parameterized
: Record() { field: Type, ... }              # anonymous/inline

Arrays

name: Type[length]     # fixed-size array
name: Type[]           # auto-sized (consumes remaining input)

Consumption

: Type              # consume without storing
name: Type          # consume and store in variable

Variables

name = expression           # assign from expression
name: Type                  # assign from consumption
name.field                  # member access
name.inner.field            # chained member access

Conditional Fields

Record Name(COND) = {
  when COND {
    field1: Type1,
    field2: Type2
  },
  field3: Type3
}

Validation

expect condition

Operators

Arithmetic

Op	Description
+ - * / %	Add, subtract, multiply, divide, modulo
-expr	Unary negation

Comparison

Op	Description
== !=	Equal, not equal
> >= < <=	Relational

Logical

Op	Description
&&	AND
||	OR
!	NOT

Builtin Functions

Function	Description
sizeof(Type)	Size in bytes (static types only)
abs(expr)	Absolute value

Comments

# single-line comment
field: Type  # inline comment