p1076_chap_04

It is an error if a constant declaration declares a

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Unformatted text preview: f a constant declaration declares a constant that is of a file type, an access type, a protected type, or a composite type that has a subelement that is a file type, an access type, or a protected type. NOTE --The subelements of a composite, declared constant are not declared constants. Examples: constant TOLERANCE : DISTANCE := 1.5 nm; constant PI : REAL := 3.141592 ; constant CYCLE_TIME : TIME := 100 ns; constant Propagation_Delay : DELAY_LENGTH; 4.3.1.2 Signal declarations A signal declaration declares a signal of the specified type. Such a signal is an explicitly declared signal. signal_declaration ::= signal identifier_list : subtype_indication [ signal_kind ] [ := expression ] ; signal_kind ::= register | bus If the name of a resolution function appears in the declaration of a signal or in the declaration of the subtype used to declare the signal, then that resolution function is associated with the declared signal. Such a signal is called a resolved signal. If a signal kind appears in a signal declaration, then the signals so declared are guarded signals of the kind indicated. For a guarded sig...
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