Institute for Computer Science

Chair IV: Software & Systems Engineering 1

How to represent Models, Languages and Transformations?

Martin Feilkas

Workshop on Domain-Specific Modeling

Oct. 22nd, 2006

Institute for Computer Science

Chair IV: Software & Systems Engineering 2

What‘s the difference?

Respresentation:

Usage:

Defined by:

textualgraphical

parsingsyntax-driven construction

grammardata model

Institute for Computer Science

Chair IV: Software & Systems Engineering 3

BNF ER

Identifier Identifier IdentifierIdentifierIdentifier

Declaration DeclarationDeclaration Expression

Statement_Block

Context-sensitive Rules

Declaration Expression

1

Identifier

n n

1

Identifier

Statement_Block

11

n n

Identifier Expressionn mDeclaration

n1

The same entity

Institute for Computer Science

Chair IV: Software & Systems Engineering 4

Consequences

• Elimination of redundant information

• ER-modeling is more expressive than context-free grammars– But still not expressive enough, so constraints are still

needed

• ER-models are easier to modify by ”ordinary” developers

• Merging: Database synchronisation instead of pattern matching

Institute for Computer Science

Chair IV: Software & Systems Engineering 5

Transformation

Transformation is a way of to specify semantic for DSLs (translational semantics)

• Nowadays:– Template-based code-generation– Weak syntax highlighting– No syntax-respecting code generation (~testing)

• Why? Generator-Backends only know that the target language is textual.

Institute for Computer Science

Chair IV: Software & Systems Engineering 6

Transformation

• Translate to the abstract and not to the concrete syntax

• No more differentiation between model-to-model and model-to-code transformation

• Syntax-driven template specification Component c insert Java-Class(Name = k.Name, Visibility="public") jk { insert Constructor(Name = jk.Name); Port (Type == "sender") p insert Method(Name = c.Name+"_"+p.Name){…}; Port (Type == "receiver") p insert Method(Name = c.Name+"_"+p.Name){…}, insert Method(Name = "CS"+c.Name+"_"+p.Name){…},

insert Attribute(Name = p.Name, Type=bool);

DataElement d GenAttr;}

GenAttr : DataElement d insert Attribute(Name = d.Name, Type=string);