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40 lines
1.1 KiB
Plaintext
40 lines
1.1 KiB
Plaintext
=== Dictionary Definitions
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If the optional keyword `dictionary` appears in a
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<<Definitions_Type-Definitions,type definition>> or
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a <<Definitions_Constant-Definitions,constant definition>>, then that
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definition is called a
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*dictionary definition*.
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A dictionary definition instructs the code generator to include
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the definition in the ground dictionary.
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==== Semantics
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If a constant definition _D_ is a dictionary definition, then the
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expression appearing in _D_ must have one of the following types:
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* A <<Types_Internal-Types_Numeric-Types,numeric type>>.
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* The <<Types_The-Boolean-Type,Boolean type>>.
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* A <<Types_String-Types,string type>>.
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* An <<Types_Enum-Types,enum type>>.
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If a type definition _D_ is a dictionary definition, then the type
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defined by _D_ must be a <<Types_Displayable-Types, displayable type>>.
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==== Examples
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[source,fpp]
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----
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dictionary type T = U32
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dictionary array A = [3] string
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dictionary constant a = 0
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enum E { X, Y }
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dictionary constant b = E.X
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type T1
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dictionary type T2 = T1 # Error: T2 is not displayable
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dictionary constant c = { x = U32 } # Error: struct type is not allowed
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----
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