CoCoA:Grammar

Base grammar

A few rules to start the formal language definition.

PROGRAM ::= $\langle$COMMAND$\rangle$ | $\Lambda$

COMMAND ::= HELP_QUERY newline
   | COMMENT
   | PACKAGE_DECL
   | FUNCTION_DECL
   | STATEMENT;

HELP_QUERY ::= ? $\langle$*$\rangle$

COMMENT ::= -- $\langle$*$\rangle$ newline
   | // $\langle$*$\rangle$ newline
   | /* $\langle$*$\rangle$ */

PACKAGE_DECL ::=
     Package PACKAGE_ID
       ${\big [}$$\langle$EXPORT_DECL ;$\rangle$${\big ]}$
       ${\big [}$$\langle$VARIABLE_DECL ;$\rangle$${\big ]}$
       ${\big [}$$\langle$FUNCTION_DECL$\rangle$${\big ]}$
     EndPackage

EXPORT_DECL ::= Export $\langle$IDENTIFIER ,$\rangle$;

VARIABLE_DECL ::= Declare $\langle$${\big [}$TYPE${\big ]}$ IDENTIFIER ,$\rangle$;

FUNCTION_DECL ::=
     Define IDENTIFIER( PARAMS ) STATEMENTS EndDefine
   | Define IDENTIFIER( PARAMS ) BuiltIn
   | Define IDENTIFIER( PARAMS ) PlugIn

PARAMS ::= $\langle$PARAM ,$\rangle$

PARAM ::= ${\big [}$TYPE${\big ]}$ IDENTIFIER

STATEMENTS ::= $\langle$STATEMENT ;$\rangle$

STATEMENT ::= $\Lambda$
   | ASSIGNMENT
   | EXPRESSION
   | FUNCTION_CALL
   | Return ${\big [}$EXPRESSION${\big ]}$
   | Print EXPRESSIONS
   | PrintLn ${\big [}$EXPRESSIONS${\big ]}$
   | If EXPRESSION Then STATEMENTS ${\big [}$ELSE_LIST${\big ]}$ EndIf
   | While EXPRESSION Do STATEMENTS EndWhile
   | Repeat STATEMENTS Until EXPRESSION
   | For IDENTIFIER := EXPRESSION To EXPRESSION ${\big [}$Step EXPRESSION${\big ]}$
   	Do STATEMENTS EndFor
   | ForEach IDENTIFIER In EXPRESSION Do STATEMENTS EndForEach
   | Break
   | Block STATEMENTS EndBlock
   | VARIABLE_DECL
   | Delete $\langle$IDENTIFIER ,$\rangle$
   | Quit

ASSIGNMENT ::= LEFT_EXPRESSION := EXPRESSION

LEFT_EXPR ::= IDENTIFIER
	| LEFT_EXPR.IDENTIFIER
	| LEFT_EXPR.[$\langle$EXPRESSION ,$\rangle$]

FUNCTION_CALL ::= FUNCTION_ID( $\langle$EXPRESSION ,$\rangle$ )

FUNCTION_ID ::= IDENTIFIER | EXPRESSION.IDENTIFIER | PACKAGE_ID.IDENTIFIER