View source for ETrice/GSoC/2012/GACL

== Generic Action Code Language (GACL)  ==

GACL is the language to describe the Detail Code for execution of ROOM Models in eTrice plugin . GACL aims at dealing with all features commonly available in imperative languages , especially Java , C/C++ . It will act as complement of current version of eTrice which uses code written in target language stored in a string as execution code . GACL would make user able to write execution code independent of target language . 

== Development Details and Core Information  ==

=== Features of GACL  ===

*Variable Declarations ( with optional initializers ) and Function Declaration . 
*Comparison &amp; arithmetic expressions . 
*Basic types , and user defined types . 
*If-else blocks and ladders . 
*For , while , for each , enhanched for each . 
*Support for iterators (that can be used by for each loops ) . 
*Function Calls with arguments &amp; diff types i.e. ref/value/address . 
*type checking and as much as possible implicit type casting . 
*Casts corresponding to static casts in C .

=== Thoughts on Syntax & Grammar ===

Although syntax for GACL is still being designed but here are few thought regarding syntax . 

==== TypeDeclaration  ====

===== Syntax =====

  type prt type xyz int
  type pqr { int Hello , char ch , prt p , op f1:int() , op f2:char(char,char) }    type pqr' {pqr e1}
  prt {pqr p};

===== Action =====

*Declares a type prt ended with whitespace 
*Creates a type xyz same as int where type declaration ended with newline 
*Creates a type pqr representing a structure rather class with abstracted elements Hello of type int , ch of char , p of type prt and f1 and f2 of type op i.e. Operations . f1 and f2 can take use of their arguments and also other elements of pqr i.e. Hello and ch in this case and ended with a tab . 
*Creates a type pqr' with e1 of pqr abstracted in it ended with newline 
*Creates prt declared already with p of type pqr abstracted in it ended with semicolon

===== Grammar =====

  { "type" typename [ existingtype | "{" TypeCode "}" ] [";" | "\n" | "\t" | " "] } | {typename typecode}

==== VariableDeclaration  ====

===== Syntax =====

  int x
  y;
  y=2    x=y
  x=x+4 y=y+0.5

===== Action =====

*Declares a variable x of type int , declaration ended with newline .
*Declares a variable y , declaration ended with semicolon .
*Instantiate a variable y with value of 2 (2 as expression) (Value of 2 would be type checked and its type would be assigned to y unless and until there exists another assignment of y with type which can be type casted into type of value) instantiation ended with "\t"
*Instantiate a variable x with value of expression y which is currently 2 . 
*Assigns variable x with value of expression x+4 which would be solved and accordingly value of x would be assigned
*Assigns variable y with value of expression x+0.5 which would be solved and accordingly value of y would be assigned (In this case type of y would be changed actually while writing it would be statically analyzed whether we need to type cast y and is it possible to type cast ) .

===== Grammar =====

  [ [[ETrice/GSoC/2012/GACL#Type_Declaration|type]] ] varname [ "=" { varname2 | [[ETrice/GSoC/2012/GACL#Expression|Expression]] } ] { ";" | "\n" | "\t" | " "}

==== Expression  ====

===== Syntax =====

  x+4
  y==z

===== Action =====

*First One is an example of arithmetic expression and would have same action as it have for an arithmetic expression .
*Second One is an example of Logical expression and it would have same action as it have for a logical expression .

===== Grammar =====

  { [[ETrice/GSoC/2012/GACL#ArithmeticExpression|ArithmeticExpression]] | [[ETrice/GSoC/2012/GACL#LogicalExpression|LogicalExpression]] }

==== ArithmeticExpression  ====

===== Syntax =====

  { [[ETrice/GSoC/2012/GACL#Expression|Expression]] { "+" | "-" | "*" | "/" | "**" | "^" | "%" | "div" } [[ETrice/GSoC/2012/GACL#Expression|Expression]] } 
 | {[[ETrice/GSoC/2012/GACL#Expression|Expression]] { "++" | "--" } } | { { "++" | "--" } [[ETrice/GSoC/2012/GACL#Expression|Expression]] }

==== LogicalExpression  ====

===== Syntax =====

===== Action =====

===== Grammar =====

  { [[ETrice/GSoC/2012/GACL#Expression|Expression]] { "&lt;" | "&lt;=" | "==" | "&gt;" | "&gt;=" | "|" | "||" | "&amp;" | "&amp;&amp;" | "^" } [[ETrice/GSoC/2012/GACL#Expression|Expression]] }

==== Statement  ====

===== Syntax =====

===== Action =====

===== Grammar =====

  { [[ETrice/GSoC/2012/GACL#TypeDeclaration|TypeDeclaration]] | [[ETrice/GSoC/2012/GACL#VariableDeclaration|VariableDeclaration]] | [[ETrice/GSoC/2012/GACL#Expression|Expression]] }

==== StatementList  ====

===== Syntax =====

===== Action =====

===== Grammar =====

  { [[ETrice/GSoC/2012/GACL#Empty|Empty]] | [[ETrice/GSoC/2012/GACL#Statement|Statement]] { { "\n" | "\t" | " "}* } [[ETrice/GSoC/2012/GACL#Statementlist|Statementlist]] }

==== Program  ====

===== Syntax =====

===== Action =====

===== Grammar =====

  { [[ETrice/GSoC/2012/GACL#Statementlist| Statementlist]] }

<br> 

== Disambiguation  ==

The syntax used to specify the grammar in brief is 

*Things written in double quotes ("") stand as string written in source . 
*Content inside braces ({}) represents required content . 
*Content inside square brackets ([]) represents optional content . 
*Everything rest is either terminal or non-terminals . 
*Empty and statement list need a more thought to be done . We would surely finally come up with a better solution .

== Project Proposal  ==

[http://www.google-melange.com/gsoc/proposal/review/google/gsoc2012/hckkid/1 Click Here] to see the project proposal at gsoc's website . 

[https://github.com/hckkid/my-eTrice-work/blob/master/Proposal.txt Click Here] to see the project proposal in my github repository . 

== Useful Links  ==

*[http://www.eclipse.org/etrice/documentation/doc/etrice.html eTrice Documentation Page] 
*[http://www.eclipse.org/Xtext/ Xtext Home Page] 
*[http://www.eclipse.org/etrice/ eTrice Home Page] 
*[http://github.com/hckkid My Github profile page] 
*[http://www.eclipse.org/forums/eclipse.etrice eTrice Forums page]

[[Category:eTrice]]