CASM language

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* Language

The CASM language is an Abstract State Machine (ASM) modeling and specification language. Its syntax][syntax is influenced in part by https://www.uni-ulm.de/in/pm/forschung/projekte/coreasm][CoreASM and other ASM languages, but includes language concepts which are well known in modern programming languages as well. Different to existing ASM implementations is that CASM is a static strong inferred typed ASM language. Before we describe various language constructs lets have a look at the /Hello World/ specification to outline the basic structure of the CASM modeling language:

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The /Hello World/ application specified in CASM: #+begin_src casm -n CASM init HelloWorld rule HelloWorld = {

  println( "Hello world!" )

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Every CASM specification starts with a Header][header containing the keyword =CASM= (line 1). The Header][header part is followed by Definitions][definitions. In line 2 an InitDefinition][init definition is specified to set the starting rule of the single execution agent to the rule named =HelloWorld=. The rule =HelloWorld= is defined in line 3 ranging to line 6 through a RuleDefinition][rule definition. Notice that CASM does not require symbol names to be declared before usage. Inside the =HelloWorld= rule a BlockRule][block rule creates a parallel execution semantics scope (line 4, 6). Last but not least the actual statement to print out the =Hello world!= string defined by a CallRule][call rule to a built-in function named =println=.

CASM does not require any newlines, tabulators, or statement separators like in other specification or programming languages.

TBA

Functions TBA # #+html:

# The following example defines a binary function named =phoneBook= with a # given type relation $x : String * String \rightarrow String$ to store # telephone number strings identified by a last and first name string: # #+begin_src casm # function phoneBook : String * String → String # #+end_src # #+html:

Rules

TBA

Initialization TBA Comments

TBA