README

SysProgLab
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Compiler for a very basic programming language - assignment in SysProg lab.

Language's symbols defined as follows:

digit ::= 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9
letter ::= A | B | C | ... | Z | a | b | ... | z
sign :: = + | − | / | ∗ | < | > | = | <=> | ! | & | ; | ( | ) | { | } | [ | ]
integer :: = digit digit∗
identifier ::= letter ( letter | digit )∗
keywords : print, read, int, if, else, while

Language's grammar defined as follows (non-terminals are with capital letters, € = empty word):
PROG ::= DECLS STATEMENTS
DECLS ::= DECL ; DECLS | €
DECL ::= int ARRAY identifier
ARRAY ::= [ integer ] | €
STATEMENTS ::= STATEMENT ; STATEMENTS | €
STATEMENT ::= identifier INDEX = EXP | print(EXP) | read (identifier INDEX) | {STATEMENTS} |
				 if(EXP) STATEMENT else STATEMENT | while(EXP) STATEMENT
EXP ::= EXP2 OP_EXP
EXP2 ::= ( EXP ) | identifier INDEX | integer | -EXP2 | !EXP2
INDEX ::= [ EXP ] | €
OP_EXP ::= OP EXP | €
OP ::= + | - | * | / | < | > | = | <=> | &


Interpreter requires the libsysprogSS2011.so file to be exported:
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:[path to library]

Run the interpreter via following command:
java -jar interpreter.jar | interpreter64.jar (for the 64bit version of the interpreter)

Note
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The compiler produces code that can only be run by the interpreter's version uploaded here (summer term 2011)


TODO
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1) Put parser's node classes in separate files like before to make the parser code more readable