Literal Values

Overview

With a typical formal model, there is a need for formal representation of literal values. This is needed to support constant declarations, 'default values' (a UML concept), enumeration literals and literal routine calls (see next section). In BMM, all such values have as their meta-type the type BMM_LITERAL_VALUE<T> or a descendant. The type hierarchy mostly mimicks parts of the BMM_TYPE meta-type hierarchy, allowing for literal values of any of the meta-types in that part of the model. The UML model is shown below.

LANG bmm.core.literal value
Figure 1. base.bmm.core.literal_value package - Literal Values

General Model

When a BMM model is instantiated in its in-memory form, e.g. in a BMM modelling tool, any literal values in the model such as constant values (e.g. Real Pi = 3.1415926), default values (e.g. Person.name: String = "(unknown)") etc are instances of 'two types':

  • their declared types withing the model, e.g. Real, String, Observation;

  • the meta-type BMM_LITERAL_VALUE<T> (or a matching descendant if there is one), which is instantiated to represent the value object within the model.

The value of any such instance is represented by the value_literal field within its BMM_LITERAL_VALUE object. This is assumed to carry a serialised form of the value expressed in a syntax known to the model processing environment within which the BMM model is being used. This may be a programming language syntax, JSON, or any other serialisable format, and is specified by BMM_LITERAL_VALUE.syntax.

Container Literals

Literals representing Lists or Sets of values of objects of other types have as their BMM meta-type BMM_CONTAINER_VALUE<T>. For example, if the serialised value ["Feyerabend", "Lakatos", "Popper"] (which happens to be a JSON Array of Strings) were parsed as a List<String> instance, its meta-type would be a BMM_CONTAINER_VALUE instance whose value_literal was the same string, assuming JSON were used as the syntax, and whose type will be BMM_CONTAINER_TYPE. Similarly a syntax that supported literal Sets using braces, e.g. {"Feyerabend", "Lakatos", "Popper"} may be parsed to a Set<String> instance, with the same meta-type as for the List.

In a similar way, a Hash table (aka 'map', 'dictionary' etc) with a formal type of Hash<K, V> has as its meta-type BMM_INDEXED_CONTAINER_VALUE.

Literal Tuples

Literal tuples may be expressed in BMM, but are not instances of BMM_LITERAL_VALUE; instead they are instances (at the meta level) of EL_TUPLE, an expression-related meta-type. This is a consequence of the fact that Tuple is considered a BMM built-in meta-type rather than a model-provided type, and also that a Tuple instance may contain items of any meta-type, not just literal values. Tuple instances are used in BMM expressions and described in [_tuples].

Type Extensions

If it were desired to create a full set of 'native' types for BMM, in the way supplied for UML in the UML Standard Profile, specific descendants would be added to the meta-type classes BMM_SIMPLE_TYPE and BMM_GENERIC_TYPE, as well as BMM_LITERAL_VALUE, which would allow such instances to be directly representable in the internal BMM type system. This would still need to be ultimately mapped to the types actually available in any language in which BMM is implemented.

Class Definitions

BMM_LITERAL_VALUE Class

  • Definition

  • Effective

  • BMM

  • UML

Class

BMM_LITERAL_VALUE (abstract)

Description

Meta-type for literal instance values declared in a model. Instance values may be inline values of primitive types in the usual fashion or complex objects in syntax form, e.g. JSON.

Inherit

BMM_TYPED

Attributes

Signature

Meaning

1..1

value_literal: `String `

A serial representation of the value.

0..1

value: `Any `

A native representation of the value, possibly derived by deserialising value_literal.

0..1

syntax: `String `

Optional specification of formalism of the value_literal attribute for complex values. Value may be any of json | yawl | xml | odin | rdf or another value agreed by the user community. If not set, json is assumed.
BMM_LITERAL_VALUE (abstract)

Meta-type for literal instance values declared in a model. Instance values may be inline values of primitive types in the usual fashion or complex objects in syntax form, e.g. JSON.

Inherits: BMM_TYPED

Attributes

type: BMM_TYPE [1..1]

Declared or inferred static type of the entity.
Inherited from BMM_TYPED

value_literal: `String ` [1..1]

A serial representation of the value.

value: `Any ` [0..1]

A native representation of the value, possibly derived by deserialising value_literal.

syntax: `String ` [0..1]

Optional specification of formalism of the value_literal attribute for complex values. Value may be any of json | yawl | xml | odin | rdf or another value agreed by the user community. If not set, json is assumed.

Functions

is_boolean (): Boolean `

Post_result: `Result = type().equal( {BMM_MODEL}.boolean_type_definition()) [1..1]

True if type is notionally Boolean (i.e. a BMM_SIMPLE_TYPE with type_name() = 'Boolean').
Inherited from BMM_TYPED

 
{
    "name": "BMM_LITERAL_VALUE",
    "documentation": "Meta-type for literal instance values declared in a model. Instance values may be inline values of primitive types in the usual fashion or complex objects in syntax form, e.g. JSON.",
    "is_abstract": true,
    "ancestors": [
        "BMM_TYPED"
    ],
    "properties": {
        "value_literal": {
            "_type": "P_BMM_SINGLE_PROPERTY",
            "name": "value_literal",
            "documentation": "A serial representation of the value.",
            "is_mandatory": true,
            "type": "String"
        },
        "value": {
            "_type": "P_BMM_SINGLE_PROPERTY",
            "name": "value",
            "documentation": "A native representation of the value, possibly derived by deserialising `_value_literal_`.",
            "type": "Any"
        },
        "syntax": {
            "_type": "P_BMM_SINGLE_PROPERTY",
            "name": "syntax",
            "documentation": "Optional specification of formalism of the `_value_literal_` attribute for complex values. Value may be any of `json | yawl | xml | odin | rdf` or another value agreed by the user community. If not set, `json` is assumed.",
            "type": "String"
        }
    }
}
bmm literal value

BMM_CONTAINER_VALUE Class

  • Definition

  • Effective

  • BMM

  • UML

Class

BMM_CONTAINER_VALUE

Description

Meta-type for literals whose concrete type is a linear container type, i.e. array, list or set.

Inherit

BMM_LITERAL_VALUE

Attributes

Signature

Meaning

1..1
(redefined)

type: BMM_CONTAINER_TYPE

Declared or inferred static type of the entity.
BMM_CONTAINER_VALUE

Meta-type for literals whose concrete type is a linear container type, i.e. array, list or set.

Inherits: BMM_TYPED, BMM_LITERAL_VALUE

Attributes

type: BMM_CONTAINER_TYPE [1..1]

Declared or inferred static type of the entity.

value_literal: `String ` [1..1]

A serial representation of the value.
Inherited from BMM_LITERAL_VALUE

value: `Any ` [0..1]

A native representation of the value, possibly derived by deserialising value_literal.
Inherited from BMM_LITERAL_VALUE

syntax: `String ` [0..1]

Optional specification of formalism of the value_literal attribute for complex values. Value may be any of json | yawl | xml | odin | rdf or another value agreed by the user community. If not set, json is assumed.
Inherited from BMM_LITERAL_VALUE

Functions

is_boolean (): Boolean `

Post_result: `Result = type().equal( {BMM_MODEL}.boolean_type_definition()) [1..1]

True if type is notionally Boolean (i.e. a BMM_SIMPLE_TYPE with type_name() = 'Boolean').
Inherited from BMM_TYPED

 
{
    "name": "BMM_CONTAINER_VALUE",
    "documentation": "Meta-type for literals whose concrete type is a linear container type, i.e. array, list or set.",
    "ancestors": [
        "BMM_LITERAL_VALUE"
    ],
    "properties": {
        "type": {
            "_type": "P_BMM_SINGLE_PROPERTY",
            "name": "type",
            "documentation": "Declared or inferred static type of the entity.",
            "is_mandatory": true,
            "type": "BMM_CONTAINER_TYPE"
        }
    }
}
bmm container value

BMM_INDEXED_CONTAINER_VALUE Class

  • Definition

  • Effective

  • BMM

  • UML

Class

BMM_INDEXED_CONTAINER_VALUE

Description

Meta-type for literals whose concrete type is an indexed container, i.e. Hash table, Map etc.

Inherit

BMM_CONTAINER_VALUE

Attributes

Signature

Meaning

1..1
(redefined)

type: BMM_INDEXED_CONTAINER_TYPE

Declared or inferred static type of the entity.
BMM_INDEXED_CONTAINER_VALUE

Meta-type for literals whose concrete type is an indexed container, i.e. Hash table, Map etc.

Inherits: BMM_TYPED, BMM_LITERAL_VALUE, BMM_CONTAINER_VALUE

Attributes

type: BMM_INDEXED_CONTAINER_TYPE [1..1]

Declared or inferred static type of the entity.

value_literal: `String ` [1..1]

A serial representation of the value.
Inherited from BMM_LITERAL_VALUE

value: `Any ` [0..1]

A native representation of the value, possibly derived by deserialising value_literal.
Inherited from BMM_LITERAL_VALUE

syntax: `String ` [0..1]

Optional specification of formalism of the value_literal attribute for complex values. Value may be any of json | yawl | xml | odin | rdf or another value agreed by the user community. If not set, json is assumed.
Inherited from BMM_LITERAL_VALUE

Functions

is_boolean (): Boolean `

Post_result: `Result = type().equal( {BMM_MODEL}.boolean_type_definition()) [1..1]

True if type is notionally Boolean (i.e. a BMM_SIMPLE_TYPE with type_name() = 'Boolean').
Inherited from BMM_TYPED

 
{
    "name": "BMM_INDEXED_CONTAINER_VALUE",
    "documentation": "Meta-type for literals whose concrete type is an indexed container, i.e. Hash table, Map etc.",
    "ancestors": [
        "BMM_CONTAINER_VALUE"
    ],
    "properties": {
        "type": {
            "_type": "P_BMM_SINGLE_PROPERTY",
            "name": "type",
            "documentation": "Declared or inferred static type of the entity.",
            "is_mandatory": true,
            "type": "BMM_INDEXED_CONTAINER_TYPE"
        }
    }
}
bmm indexed container value

BMM_UNITARY_VALUE Class

  • Definition

  • Effective

  • BMM

  • UML

Class

BMM_UNITARY_VALUE (abstract)

Description

Meta-type for literals whose concrete type is a unitary type in the BMM sense.

Inherit

BMM_LITERAL_VALUE

Attributes

Signature

Meaning

1..1
(redefined)

type: BMM_UNITARY_TYPE

Declared or inferred static type of the entity.
BMM_UNITARY_VALUE (abstract)

Meta-type for literals whose concrete type is a unitary type in the BMM sense.

Inherits: BMM_TYPED, BMM_LITERAL_VALUE

Attributes

type: BMM_UNITARY_TYPE [1..1]

Declared or inferred static type of the entity.

value_literal: `String ` [1..1]

A serial representation of the value.
Inherited from BMM_LITERAL_VALUE

value: `Any ` [0..1]

A native representation of the value, possibly derived by deserialising value_literal.
Inherited from BMM_LITERAL_VALUE

syntax: `String ` [0..1]

Optional specification of formalism of the value_literal attribute for complex values. Value may be any of json | yawl | xml | odin | rdf or another value agreed by the user community. If not set, json is assumed.
Inherited from BMM_LITERAL_VALUE

Functions

is_boolean (): Boolean `

Post_result: `Result = type().equal( {BMM_MODEL}.boolean_type_definition()) [1..1]

True if type is notionally Boolean (i.e. a BMM_SIMPLE_TYPE with type_name() = 'Boolean').
Inherited from BMM_TYPED

 
{
    "name": "BMM_UNITARY_VALUE",
    "documentation": "Meta-type for literals whose concrete type is a unitary type in the BMM sense.",
    "is_abstract": true,
    "ancestors": [
        "BMM_LITERAL_VALUE"
    ],
    "properties": {
        "type": {
            "_type": "P_BMM_SINGLE_PROPERTY",
            "name": "type",
            "documentation": "Declared or inferred static type of the entity.",
            "is_mandatory": true,
            "type": "BMM_UNITARY_TYPE"
        }
    }
}
bmm unitary value

BMM_PRIMITIVE_VALUE Class

  • Definition

  • Effective

  • BMM

  • UML

Class

BMM_PRIMITIVE_VALUE

Description

Meta-type for literals whose concrete type is a primitive type.

Inherit

BMM_UNITARY_VALUE

Attributes

Signature

Meaning

1..1
(redefined)

type: BMM_SIMPLE_TYPE

Declared or inferred static type of the entity.
BMM_PRIMITIVE_VALUE

Meta-type for literals whose concrete type is a primitive type.

Inherits: BMM_TYPED, BMM_LITERAL_VALUE, BMM_UNITARY_VALUE

Attributes

type: BMM_SIMPLE_TYPE [1..1]

Declared or inferred static type of the entity.

value_literal: `String ` [1..1]

A serial representation of the value.
Inherited from BMM_LITERAL_VALUE

value: `Any ` [0..1]

A native representation of the value, possibly derived by deserialising value_literal.
Inherited from BMM_LITERAL_VALUE

syntax: `String ` [0..1]

Optional specification of formalism of the value_literal attribute for complex values. Value may be any of json | yawl | xml | odin | rdf or another value agreed by the user community. If not set, json is assumed.
Inherited from BMM_LITERAL_VALUE

Functions

is_boolean (): Boolean `

Post_result: `Result = type().equal( {BMM_MODEL}.boolean_type_definition()) [1..1]

True if type is notionally Boolean (i.e. a BMM_SIMPLE_TYPE with type_name() = 'Boolean').
Inherited from BMM_TYPED

 
{
    "name": "BMM_PRIMITIVE_VALUE",
    "documentation": "Meta-type for literals whose concrete type is a primitive type.",
    "ancestors": [
        "BMM_UNITARY_VALUE"
    ],
    "properties": {
        "type": {
            "_type": "P_BMM_SINGLE_PROPERTY",
            "name": "type",
            "documentation": "Declared or inferred static type of the entity.",
            "is_mandatory": true,
            "type": "BMM_SIMPLE_TYPE"
        }
    }
}
bmm primitive value

BMM_STRING_VALUE Class

  • Definition

  • Effective

  • BMM

  • UML

Class

BMM_STRING_VALUE

Description

Meta-type for a literal String value, for which type is fixed to the BMM_TYPE representing String and value is of type String.

Inherit

BMM_PRIMITIVE_VALUE

Attributes

Signature

Meaning

1..1
(redefined)

value: `String `

Native String value.
BMM_STRING_VALUE

Meta-type for a literal String value, for which type is fixed to the BMM_TYPE representing String and value is of type String.

Inherits: BMM_TYPED, BMM_LITERAL_VALUE, BMM_UNITARY_VALUE, BMM_PRIMITIVE_VALUE

Attributes

type: BMM_SIMPLE_TYPE [1..1]

Declared or inferred static type of the entity.
Inherited from BMM_PRIMITIVE_VALUE

value_literal: `String ` [1..1]

A serial representation of the value.
Inherited from BMM_LITERAL_VALUE

value: `String ` [1..1]

Native String value.

syntax: `String ` [0..1]

Optional specification of formalism of the value_literal attribute for complex values. Value may be any of json | yawl | xml | odin | rdf or another value agreed by the user community. If not set, json is assumed.
Inherited from BMM_LITERAL_VALUE

Functions

is_boolean (): Boolean `

Post_result: `Result = type().equal( {BMM_MODEL}.boolean_type_definition()) [1..1]

True if type is notionally Boolean (i.e. a BMM_SIMPLE_TYPE with type_name() = 'Boolean').
Inherited from BMM_TYPED

 
{
    "name": "BMM_STRING_VALUE",
    "documentation": "Meta-type for a literal String value, for which `_type_` is fixed to the `BMM_TYPE` representing `String` and `_value_` is of type `String`.",
    "ancestors": [
        "BMM_PRIMITIVE_VALUE"
    ],
    "properties": {
        "value": {
            "_type": "P_BMM_SINGLE_PROPERTY",
            "name": "value",
            "documentation": "Native String value.",
            "is_mandatory": true,
            "type": "String"
        }
    }
}
bmm string value

BMM_INTEGER_VALUE Class

  • Definition

  • Effective

  • BMM

  • UML

Class

BMM_INTEGER_VALUE

Description

Meta-type for a literal Integer value, for which type is fixed to the BMM_TYPE representing Integer and value is of type Integer.

Inherit

BMM_PRIMITIVE_VALUE

Attributes

Signature

Meaning

1..1
(redefined)

value: `Integer `

Native Integer value.
BMM_INTEGER_VALUE

Meta-type for a literal Integer value, for which type is fixed to the BMM_TYPE representing Integer and value is of type Integer.

Inherits: BMM_TYPED, BMM_LITERAL_VALUE, BMM_UNITARY_VALUE, BMM_PRIMITIVE_VALUE

Attributes

type: BMM_SIMPLE_TYPE [1..1]

Declared or inferred static type of the entity.
Inherited from BMM_PRIMITIVE_VALUE

value_literal: `String ` [1..1]

A serial representation of the value.
Inherited from BMM_LITERAL_VALUE

value: `Integer ` [1..1]

Native Integer value.

syntax: `String ` [0..1]

Optional specification of formalism of the value_literal attribute for complex values. Value may be any of json | yawl | xml | odin | rdf or another value agreed by the user community. If not set, json is assumed.
Inherited from BMM_LITERAL_VALUE

Functions

is_boolean (): Boolean `

Post_result: `Result = type().equal( {BMM_MODEL}.boolean_type_definition()) [1..1]

True if type is notionally Boolean (i.e. a BMM_SIMPLE_TYPE with type_name() = 'Boolean').
Inherited from BMM_TYPED

 
{
    "name": "BMM_INTEGER_VALUE",
    "documentation": "Meta-type for a literal Integer value, for which `_type_` is fixed to the `BMM_TYPE` representing `Integer` and `_value_` is of type `Integer`.",
    "ancestors": [
        "BMM_PRIMITIVE_VALUE"
    ],
    "properties": {
        "value": {
            "_type": "P_BMM_SINGLE_PROPERTY",
            "name": "value",
            "documentation": "Native Integer value.",
            "is_mandatory": true,
            "type": "Integer"
        }
    }
}
bmm integer value

BMM_BOOLEAN_VALUE Class

  • Definition

  • Effective

  • BMM

  • UML

Class

BMM_BOOLEAN_VALUE

Description

Meta-type for a literal Boolean value, for which type is fixed to the BMM_TYPE representing Boolean and value is of type Boolean.

Inherit

BMM_PRIMITIVE_VALUE

Attributes

Signature

Meaning

1..1
(redefined)

value: `Boolean `

Native Boolean value.
BMM_BOOLEAN_VALUE

Meta-type for a literal Boolean value, for which type is fixed to the BMM_TYPE representing Boolean and value is of type Boolean.

Inherits: BMM_TYPED, BMM_LITERAL_VALUE, BMM_UNITARY_VALUE, BMM_PRIMITIVE_VALUE

Attributes

type: BMM_SIMPLE_TYPE [1..1]

Declared or inferred static type of the entity.
Inherited from BMM_PRIMITIVE_VALUE

value_literal: `String ` [1..1]

A serial representation of the value.
Inherited from BMM_LITERAL_VALUE

value: `Boolean ` [1..1]

Native Boolean value.

syntax: `String ` [0..1]

Optional specification of formalism of the value_literal attribute for complex values. Value may be any of json | yawl | xml | odin | rdf or another value agreed by the user community. If not set, json is assumed.
Inherited from BMM_LITERAL_VALUE

Functions

is_boolean (): Boolean `

Post_result: `Result = type().equal( {BMM_MODEL}.boolean_type_definition()) [1..1]

True if type is notionally Boolean (i.e. a BMM_SIMPLE_TYPE with type_name() = 'Boolean').
Inherited from BMM_TYPED

 
{
    "name": "BMM_BOOLEAN_VALUE",
    "documentation": "Meta-type for a literal Boolean value, for which `_type_` is fixed to the `BMM_TYPE` representing `Boolean` and `_value_` is of type `Boolean`.",
    "ancestors": [
        "BMM_PRIMITIVE_VALUE"
    ],
    "properties": {
        "value": {
            "_type": "P_BMM_SINGLE_PROPERTY",
            "name": "value",
            "documentation": "Native Boolean value.",
            "is_mandatory": true,
            "type": "Boolean"
        }
    }
}
bmm boolean value

BMM_INTERVAL_VALUE Class

  • Definition

  • Effective

  • BMM

  • UML

Class

BMM_INTERVAL_VALUE

Description

Meta-type for literal intervals of type Interval<Ordered>.

Inherit

BMM_LITERAL_VALUE
BMM_INTERVAL_VALUE

Meta-type for literal intervals of type Interval<Ordered>.

Inherits: BMM_TYPED, BMM_LITERAL_VALUE

Attributes

type: BMM_TYPE [1..1]

Declared or inferred static type of the entity.
Inherited from BMM_TYPED

value_literal: `String ` [1..1]

A serial representation of the value.
Inherited from BMM_LITERAL_VALUE

value: `Any ` [0..1]

A native representation of the value, possibly derived by deserialising value_literal.
Inherited from BMM_LITERAL_VALUE

syntax: `String ` [0..1]

Optional specification of formalism of the value_literal attribute for complex values. Value may be any of json | yawl | xml | odin | rdf or another value agreed by the user community. If not set, json is assumed.
Inherited from BMM_LITERAL_VALUE

Functions

is_boolean (): Boolean `

Post_result: `Result = type().equal( {BMM_MODEL}.boolean_type_definition()) [1..1]

True if type is notionally Boolean (i.e. a BMM_SIMPLE_TYPE with type_name() = 'Boolean').
Inherited from BMM_TYPED

 
{
    "name": "BMM_INTERVAL_VALUE",
    "documentation": "Meta-type for literal intervals of type `Interval<Ordered>`.",
    "ancestors": [
        "BMM_LITERAL_VALUE"
    ]
}
bmm interval value