Duration v1 (X7DU)

Module: ext.time.duration

Wire encoding (bytes doc)

A Duration is represented as a small tagged bytes document.

OK doc (tag = 1)

Byte layout (little-endian):

Offset	Size	Field	Type	Notes
0	1	tag	u8	must be 1
1	1	ver	u8	must be 1
2	4	secs_lo	u32	low 32 bits of signed i64 seconds (two’s complement)
6	4	secs_hi	u32	high 32 bits of signed i64 seconds (two’s complement)
10	4	nanos	u32	must be < 1_000_000_000

The value is: secs_i64 + nanos/1e9.

ERR doc (tag = 0)

Offset	Size	Field	Type	Notes
0	1	tag	u8	must be 0
1	4	err_code	u32	see below
5	4	reserved	u32	must be 0

Error codes (v1)

Pinned numeric meanings:

• SPEC_ERR_DUR_TRUNCATED = 1 — doc too short
• SPEC_ERR_DUR_BAD_TAG = 2 — tag is not 0/1
• SPEC_ERR_DUR_BAD_VER = 3 — ok doc but ver != 1
• SPEC_ERR_DUR_BAD_NANOS = 4 — nanos >= 1e9
• SPEC_ERR_DUR_RANGE = 5 — i64 overflow/underflow during normalization or arithmetic

Canonical API (v1)

Constructors:

• ext.time.duration.from_secs_i32_v1(secs: i32) -> bytes
• ext.time.duration.from_secs_u32_v1(secs_u32: i32) -> bytes
• ext.time.duration.from_nanos_v1(nanos_u32: i32) -> bytes
• ext.time.duration.make_v1(secs_lo: i32, secs_hi: i32, nanos_u32: i32) -> bytes
  • Normalizes nanos carry/borrow and returns an OK/ERR doc.

Arithmetic:

• add_v1(a: bytes, b: bytes) -> bytes
• sub_v1(a: bytes, b: bytes) -> bytes

Accessors:

• is_err_v1(doc: bytes_view) -> i32
• err_code_v1(doc: bytes_view) -> i32
• ver_v1(doc: bytes_view) -> i32
• secs_lo_v1(doc: bytes_view) -> i32
• secs_hi_v1(doc: bytes_view) -> i32
• nanos_v1(doc: bytes_view) -> i32

All accessors are total: for malformed docs, they return deterministic defaults and/or SPEC_ERR_* via err_code_v1.