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5.22.6 Forth200x Structures

The Forth 200x standard defines a slightly less convenient form of structures. In general (when using field+, you have to perform the alignment yourself, but there are a number of convenience words (e.g., field: that perform the alignment for you.

A typical usage example is:

     0
       field:                   s-a
       faligned 2 floats +field s-b
     constant s-struct

An alternative way of writing this structure is:

     begin-structure s-struct
       field:                   s-a
       faligned 2 floats +field s-b
     end-structure

begin-structure       "name" – struct-sys 0         X:structures       “begin-structure”

end-structure       struct-sys +n –         X:structures       “end-structure”

+field       n1 n2 "name" – n3         X:structures       “plus-field”

cfield:       u1 "name" – u2         X:structures       “cfield:”

field:       u1 "name" – u2         X:structures       “field:”

2field:       u1 "name" – u2         gforth       “2field:”

ffield:       u1 "name" – u2         X:structures       “ffield:”

sffield:       u1 "name" – u2         X:structures       “sffield:”

dffield:       u1 "name" – u2         X:structures       “dffield:”