BASIC

INTRO

GRAMMAR


Unary_Op 	::= 	-    |    !
Binary_Op 	::= 	+    |    -    |    *    |    /    |    %
	  	| 	=    |    <    |    >    |    <=   |    >=    |    <>
  		| 	&    |    '    |    '
Expression 	::= 	integer
  		| 	variable
  		| 	"string"
  		| 	Unary_Op   Expression
  		| 	Expression   Binary_Op   Expression
  		| 	( Expression )
Command 	::= 	REM string
  		| 	GOTO integer
  		| 	LET variable = Expression
  		| 	PRINT Expression
  		| 	INPUT variable
  		| 	IF Expression THEN integer
 
Line 		::= 	integer Command
 
Program 	::= 	Line
  		| 	Line Program
 
Phrase 		::= 	Line | RUN | LIST | END