"STRUCT - simple struct implementation"

struct
"struct" implements neon/mops/mpe-like structures.
"structs" implements fsl/mforth-like structures.

the two wordsets are designed to let the sub-words
to be used interchangably both inside STRUCT and
STRUCTURE definitions. They will also work inside
pfe's class-definitions btw.

The provided words try to be compatible
with the simple implementation guidelines as
provided in the survey at the comp.lang.forth.repository
(http://forth.sourceforge.net/word/structure)
and the documentation on MPE' forth's implementation
(/vol/c/Programme/PfwVfx/Doc/VfxMan.Htm/struct.html)
and the structs-source of the Forth Scientific Library
(lib/fsl/structs.fth)
plus some compatibility sugar for the gforth' struct
(gforth/struct.fs)

field-layout
PFA[0] has the offset (elsewhere for the method-table)
PFA[1] has the sizeof (may serve as minimalistic type-id)

struct-layout
PFA[0] unused (elswehere method-table or type-id)
PFA[1] has the sizeof (that is instantiated)

therefore SIZEOF is designed to give a nice result in
both places.
EXTENSIONS
NEON-MOPS-MPE variant
EXTENSIONS STRUCT

no special info, see general notes

struct loader code P4_FXco

EXTENSIONS END-STRUCT

no special info, see general notes

struct loader code P4_FXco

EXTENSIONS FIELD

no special info, see general notes

struct loader code P4_RTco

EXTENSIONS SUBRECORD

no special info, see general notes

struct loader code P4_FXco

EXTENSIONS END-SUBRECORD

no special info, see general notes

struct loader code P4_FXco

EXTENSIONS ARRAY-OF

no special info, see general notes

struct loader code P4_FXco

EXTENSIONS VARIANT

no special info, see general notes

struct loader code P4_FXco

EXTENSIONS END-VARIANT

no special info, see general notes

struct loader code P4_FXco

EXTENSIONS INSTANCE

no special info, see general notes

struct loader code P4_FXco

EXTENSIONS INSTANCE-ADDR

no special info, see general notes

struct loader code P4_FXco

traditional wording
EXTENSIONS STRUCTURE

no special info, see general notes

struct loader code P4_RTco

EXTENSIONS ENDSTRUCTURE

no special info, see general notes

struct loader code P4_FXco

EXTENSIONS SIZEOF

no special info, see general notes

struct loader code P4_SXco

gforth compatibility
EXTENSIONS CHAR%

no special info, see general notes

struct loader code P4_FXco

EXTENSIONS CELL%

no special info, see general notes

struct loader code P4_FXco

EXTENSIONS WCHAR%

no special info, see general notes

struct loader code P4_FXco

EXTENSIONS DOUBLE%

no special info, see general notes

struct loader code P4_FXco

EXTENSIONS FLOAT%

no special info, see general notes

struct loader code P4_FXco

EXTENSIONS SFLOAT%

no special info, see general notes

struct loader code P4_FXco

EXTENSIONS DFLOAT%

no special info, see general notes

struct loader code P4_FXco