The document describes aspects of creating and defining a domain-specific language in MPS, including defining concepts, structure, editors, and relationships between concepts. Key concepts include Entity, Field, and Statement. Concepts can be abstract, extended by subconcepts, and implemented as interfaces. Editors are defined for concepts. The language is played with and compiled in a sandbox solution.

1. MPS
concept notion of a language
aspects structure
editor
constraints
behavior
typesystem
for example, Entity
generator
actions
intentions
concepts of a language
and more
describes abstract structure
of a syntax element
visual representation of concepts
restrictions on concepts and their relationships
methods of concepts
inference and validation of types of concepts
translation of concepts into another language
advanced editor behavior
quickfixes

2. Creating a new language

3. Aspects of the language
creating concept
Entity

4. Structure Aspect creating concept “Entity” Entity has name
reference to the super-concept
reference to interface concepts that current concept implements
whether the concept can be used at AST root node
text in the right of the auto-completion menu – helps users
distinguish among concepts that share the same alias
properties are values owned by the concept
children define aggregation relationships between the concept and its possible parts
references can point to AST nodes that are not connected the concept via aggregation
string that it would be natural
to type when trying to create
an instance of the concept
“trigger”

5. Building the language playing with sandbox solution
keyword entity can’t be edited
editor in use
“compiling” the language
creating an instance of entity
in the sandbox solution

6. Structure Aspect creating concept “Field” Field has name
typing “field” in the projectional editor
will create an instance of concept Field
and show its projection
can have fieldsentity

7. Editor Aspect creating editors for concepts “Entity”, “Field”
creating editor for a concept
intentions
editor definition for Entity (statement-like)
editor definition for Field (statement-like)
editor in use
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8. Editor Aspect
horizontal collection
vertical collection

9. Concepts interface implementation
INamedConcept is an interface concept
that has property name of type string
INamedConcept is an interface concept
that has property name of type string
explicit declaration of property name is removed

10. Subconcepts inheritance
number fieldfield
text field
toggle field
make concept Field abstractvia intentions menu
alias of abstract concept – removed
number field text field toggle field
extend concept Field
make
abstract concepts cannot be instantiated
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11. Subconcepts inheritance
concept NumberField extends
abstract concept Field
concept TextField extends Field concept ToggleField extends Field
statement-like editor
editor in use
autocompletion menu provided by MPS
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12. Structure Aspect concepts for statements
print statementstatement
assignment statement
Statement – abstract concept
Entity can have Statement’s
can be made an interface conceptStatement

13. Structure Aspect concepts for statements
editor in use
temporary solution
(will be replaced by
concept Expression)
concept PrintableValue
encapsulates a string value
PrintStatement extends
abstract concept Statement
projection of PrintableValue
is value itself
value is “hi”
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