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Appendix J
checks-lisp
This appendix gives some comment on the Philgram realization of the context checks
that are defined in the environment, given by appendix I.
<ADDING-SIMPLE> ==>
Allowed sub-object types are given by appendix G.
<ADD-SIMPLE> ==>
Allowed sub-object types are given by appendix G.
<ASSIGN STAT> ==>
The type variables in the variable-list depend on the type of
the expression. See table J .1.
I
variable
REAL
REAL
INTEGER
BOOLEAN
CHAR
INTEGER
CHAR
ENUMERATED
SET
expression
REAL
INTEGER
INTEGER
BOOLEAN
CHAR
INTEGER
CHAR
ENUMERATED
type( expression)
subranges of
subranges of
subranges of
basetypes are equal or empty sets ,
Table J.t: Assignment statement.
Assignments of a value to a subrange type variable that exceed the limit of the subrange
mayor may not result in an error. This depends on the host-computer system. Rangechecks are therefore not defined in the context layer specification of HHDL. Wrong
assignments should however be detected by the environment. Range-check evaluators
should therefore be defined.
<CASE_OF -STAT> ==>
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