Basic DSL
The platform independent DSL “Basic” defines basic module types, element types, member types and options, that are going to be reused in other DSLs (e.g. “Persistence”). Here is the overview on all defined types.
| Module-Types | Element-Types | Member-Types |
|---|---|---|
| Basic | type | field |
| Basic | enumeration | entry |
In the following the types and their options are going to be described in more detail.
Module-Types¶
Basic¶
For all types and options it is necessary to set the module type “Basic” with a module’s “kind” attribute.
Example:
...
module MyModule kind = Basic;
...
Options for Module-Type “Basic”
| Option | Option-Type | Description |
|---|---|---|
| no options defined | - | - |
Element-Types¶
type¶
A “type” element is going to be used to define a type. This is similar to a type definition in programming languages. DSLs, that define element types that inherit from “type”, automatically get the capability to model “fields”.
Example:
type Item {
field name : Text;
}
Options for Element-Type “type”
| Option | Option-Type | Description |
|---|---|---|
| no options defined | - | - |
Members and Member-Options for Element-Type “type”
Member: field
A “field” is, as the name implies, a field of a type. In programming languages there are other well-known terms for “field”: “property”, “attribute”. “fields” that are modeled with the DSL “Basic” have a similar meaning like in programming languages.
| Option | Option-Type | Description |
|---|---|---|
| CollectionType | Enumerated, single valued | Possible value: Array, List, Set, SortedSet |
| EqualityRelevance | Boolean | Defines, if a “field” is relevant when two different types are compared with each other. |
| ReadOnly | Boolean | Defines, whether a “field” can only be read but not be modified. |
| DefaultValue | Quoted Text | Defines a default value for a “field”, that should be used to initialize it. |
| MultiplicityType | Enumerated, single valued | Possible value: OneToOne, OneToN, NToOne, MToN |
| Cardinality | Numeric | Defines, how many elements a “field” can hold, when it has the CollectionType “Array” set. |
type - Predefined Types¶
The installation of the DSL “Basic” additionally includes some predefined “type” model elements. A generator maps these elements to platform specific types. You can define aliases for all of those predefined types. A guide and a sample can be found in the users guide.
Here you can see the predefined “type” elements.
| Predefined Type | Description |
|---|---|
| Date | Date, Year, Month or Day |
| Datetime | Date and Time |
| Time | Time, Hours, Minutes, Seconds, Milliseconds |
| character | one single Character |
| float128 | signed Floating Point Number with 16 Bytes, a Java BigDecimal for instance |
| float64 | signed Floating Point Number with 8 Bytes, a Java double or Delphi Double for instance |
| float32 | signed Floating Point Number with 4 Bytes, a Java float or Delphi Single for instance |
| float16 | signed Floating Point Number with 2 Bytes |
| sint128 | signed Integer with 16 Bytes |
| sint64 | signed Integer with 8 Bytes, a Java long oder Delphi Int64 for instance |
| sint32 | signed Integer with 4 Bytes, a Java int oder Delphi Integer for instance |
| sint16 | signed Integer with 2 Bytes, a Java short oder Delphi SmallInt for instance |
| sint8 | signed Integer with 1 Byte, a Java int oder Delphi ShortInt for instance |
| string | a String, a Collection of Characters |
| uint128 | unsigned Integer with 16 Bytes |
| uint64 | unsigned Integer with 8 Bytes, a Java BigDecimal or Delphi UInt64 for instance |
| uint32 | unsigned Integer with 4 Bytes, a Java long or Delphi Cardinal for instance |
| uint16 | unsigned Integer with 2 Bytes, a Java int or Delphi Word for instance |
| uint8 | unsigned Integer with 1 Byte, a Java short or Delphi Byte for instance |
| uint1 | a Bit, a Java boolean or Delphi Boolean for instance |
enumeration¶
As the name implies, an “enumeration” is used to define an enumeration. Enumerations typically are going to be used as type of a “field”. Again similar to programming languages.
Example:
enumeration Gender {
entry MALE;
entry FEMALE;
}
Options for Element-Type “enumeration”
| Option | Option-Type | Description |
|---|---|---|
| no options defined | - | - |
Members and Member-Options for Element-Type “enumeration”
Member: entry
An “entry” defines an enumeration value in an enumeration.
| Option | Option-Type | Description |
|---|---|---|
| no options defined | - | - |
Member: field
see above, members of “type”
| Option | Option-Type | Description |
|---|---|---|
| no options defined | - | - |