10.6.2.0135 +FIELD plus-field FACILITY EXT

( n₁ n₂ "<spaces>name" -- n₃ )

Skip leading space delimiters. Parse name delimited by a space. Create a definition for name with the execution semantics defined below. Return n₃ = n₁ + n₂ where n₁ is the offset in the data structure before +FIELD executes, and n₂ is the size of the data to be added to the data structure. n₁ and n₂ are in address units.

( addr₁ -- addr₂ )

Add n₁ to addr₁ giving addr₂.

10.6.2.0763 BEGIN-STRUCTURE, 10.6.2.1336 END-STRUCTURE,
10.6.2.0893 CFIELD:, 10.6.2.1518 FIELD:, 12.6.2.1517 FFIELD:,
12.6.2.2206.40 SFFIELD:, 12.6.2.1207.40 DFFIELD:, A.10.6.2.0135 +FIELD.

+FIELD is not required to align items. This is deliberate and allows the construction of unaligned data structures for communication with external elements such as a hardware register map or protocol packet. Field alignment has been left to the appropriate xFIELD: definition.

Create a new field within a structure definition of size n bytes.

: +FIELD  \ n <"name"> -- ; Exec: addr -- 'addr
   CREATE OVER , +
   DOES> @ +
;