Category:Elena Implementations: Difference between revisions

{{implementation|Brainf***}}{{collection|RCBF}}

<lang elena>#define system.

#define extensions'text.

// --- Tape ---

#class Tape

{

#field theArray.

#field thePointer.

#constructor new &type'length:aLength

[

thePointer := Integer new:0.

theArray := Array new &type'length:aLength &function: &&:n [ Integer new:0 ].

]

#method type'tape = $self.

#method append

[

(theArray@thePointer) += 1.

]

#method reduce

[

(theArray@thePointer) -= 1.

]

#method next

[

thePointer += 1.

]

#method previous

[

thePointer -= 1.

]

#method input

[

(theArray@thePointer) write &type'int:(console readChar).

]

#method output

[

console write:(CharValue new:(theArray@thePointer)).

]

#method get = theArray@thePointer.

}

// --- LoopInterpreter ---

#class LoopInterpreter

{

#field theLoopBody.

#field theTape.

#constructor new &tape:aTape

[

theTape := aTape.

theLoopBody := String new.

]

#method type'tape = theTape type'tape.

#method append

[

theLoopBody += "+".

]

#method reduce

[

theLoopBody += "-".

]

#method next

[

theLoopBody += ">".

]

#method previous

[

theLoopBody += "<".

]

#method input

[

theLoopBody += ",".

]

#method output

[

theLoopBody += ".".

]

#method run

[

control while:[0 < theTape get ] &do:

[ interpreter'Interpreter new:(theTape type'tape) eval:theLoopBody. ].

^ theTape.

]

}

// --- Interpreter ---

#class Interpreter

{

#field theTape.

#constructor new : aTape

[

theTape := aTape.

]

#method eval : anObject

[

$self eval::anObject.

]

#method eval &type'widestr:aLiteral

[

control foreach:aLiteral &do:$self.

]

#method eval &type'widechar:aChar

[

aChar =>

">" ? [ theTape next ]

"<" ? [ theTape previous ]

"+" ? [ theTape append ]

"-" ? [ theTape reduce ]

"." ? [ theTape output. ]

"," ? [ theTape input. ]

"[" ? [ theTape := LoopInterpreter new &tape:theTape. ]

"]" ? [ theTape := theTape run. ].

]

}

// --- Program ---

#symbol program =

[

('program'arguments Count == 1)?

[ console write:"Please provide the path to the file to interpret". #throw BreakException new. ].

textFileControl forEachLine:('program'arguments@1) &do:(Interpreter new:(Tape new &type'length:1024)).

].</lang>