truffle-framework compiler microjava microjavacompiler graalvm

MicroJava++ 🐧

Implementation of the programming language compiler. Based on the Truffle framework. MicroJava as the base grammar for MicroJava++

Language description

Grammar

Also known as MicroJava - Grammatik 👽

Program = "program" ident { ConstDecl | VarDecl | ClassDecl } "{" {MethodDecl} "}". 

ConstDecl = "final" Type ident "=" ( number | charConst ) ";". 

VarDecl = Type ident { "," ident } ";". 

ClassDecl = "class" ident "{" { VarDecl } "}". 

MethodDecl = ( T  ype | "void" ) ident "(" [ FormPars ] ")" { V  arDecl } Block. 

FormPars = Type ident { "," Type ident }. Type = ident [ "[" "]" ]. 

Block = "{" { Statement } "}". 

Statement = Designator ( Assignop Expr | ActPars | "++" | "--" ) ";" 
            | "if" "(" Condition ")" Statement [ "else" Statement ] 
            | "while" "(" Condition ")" Statement 
            | "break" ";" | "continue" ";" 
            | "return" [ Expr ] ";" 
            | "read" "(" Designator ")" ";" 
            | "print" "(" Expr [ "," number ] ")" ";" 
            | Block 
            | ";". 

Assignop = "=" | "+=" | "-=" | "*=" | "/=" | "%=". 

ActPars = "(" [ Expr { "," Expr } ] ")". 

Condition = CondTerm { "||" CondTerm }. 

CondTerm = CondFact { "&&" CondFact }. 

CondFact = Expr Relop Expr. Relop = "==" | "!=" | ">" | ">=" | "<" | "<=". 

Expr = [ "–" ] Term { Addop Term }. Term = Factor { Mulop Factor }. 

Factor = Designator [ ActPars ] 
         | number 
         | charConst 
         | "new" ident [ "[" Expr "]" ]
         | "(" Expr ")". 
         
Designator = ident { "." ident | "[" Expr "]" }.

Addop = "+" | "–". 

Mulop = "*" | "/" | "%".

Extensions 💰

MicroJava++ supports additional features, not sated in the grammar:

Scoping (Functions` and blocks` scopes, we are very proud of this! 🙌);
Declaring variables inside of funtions/blocks;
Declaring constant variables inside the functions/blocks;
Constant variables can be initialized with expression, not only literal (inside of the block, global variables suport only literal initilization);
Supported types: Integer, Boolean, Character, Double;

Not implemented yet ⏩

Arrays - Nodes for arrays were implemented, but to work corectly with scoping system, there is still work to be done;
Classes - TBD;
For/Foreach - After adding arrays, to make work with them more convinient;
auto keyword - For type deduction;
Ternary operator - The functional way, is the righ way;