CoCoA:Grammar

Base grammar

A few rules to start the formal language definition. (They will slowly get more readable as soon as I get confidence with the wiki)

PROGRAM ::= <COMMAND> | $\Lambda$

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

HELP_QUERY ::= ? $\langle$*$\rangle$

PACKAGE_DECL ::= Package PACKAGE_ID <FUNCTION_DECL> End[Package]

FUNCTION_DECL ::= Define IDENTIFIER(PARAMS) STATEMENTS End[Define]
	| Define [Internal/External] IDENTIFIER(PARAMS)

PARAMS ::= <PARAM ,>

PARAM ::= [ TYPE ] IDENTIFIER

STATEMENT ::= $\Lambda$
	| ASSIGNMENT
	| EXPRESSION
	| FUNCTION_CALL
	| Return [ EXPRESSION ]
	| Print EXPRESSIONS
	| PrintLn [ EXPRESSIONS ]
	| If EXPRESSION Then STATEMENTS [ ELSE_LIST ] End[If]
	| While EXPRESSION Do STATEMENTS End[While]
	| Repeat STATEMENTS Until EXPRESSION
	| For IDENTIFIER := EXPRESSION To EXPRESSION [ Step EXPRESSION ]
		Do STATEMENTS End[For]
	| ForEach IDENTIFIER In EXPRESSION Do STATEMENTS End[ForEach]
	| Break
	| Block STATEMENTS End[Block]
	| Declare [ TYPE ] <IDENTIFIER ,>
	| Delete <IDENTIFIER ,>
	| Quit

ASSIGNMENT ::= LEFT_EXPRESSION := EXPRESSION

LEFT_EXPR ::= IDENTIFIER
	| LEFT_EXPR.IDENTIFIER
	| LEFT_EXPR.[<EXPRESSION ,>]

FUNCTION_CALL ::= FUNCTION_ID(<EXPRESSION ,>)

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