100 lines
2.1 KiB
Text
100 lines
2.1 KiB
Text
class Cell {
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init(previous, next, data) {
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this.previous = previous;
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this.next = next;
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this.data = data;
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}
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}
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class Tape {
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init() {
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this.current = Cell(nil, nil, 0);
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}
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backward() {
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if (this.current.previous == nil) {
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this.current.previous = Cell(nil, this.current, 0);
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}
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this.current = this.current.previous;
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}
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forward() {
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if (this.current.next == nil) {
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this.current.next = Cell(this.current, nil, 0);
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}
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this.current = this.current.next;
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}
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increment() {
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this.current.data = this.current.data + 1;
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}
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decrement() {
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this.current.data = this.current.data - 1;
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}
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}
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class Interpreter {
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init(bfpath) {
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this.bfpath = bfpath;
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}
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run() {
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var tape = Tape();
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var instruction = read(this.bfpath);
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while (instruction != nil) {
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if (instruction == ">") {
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tape.forward();
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}
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if (instruction == "<") {
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tape.backward();
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}
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if (instruction == "+") {
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tape.increment();
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}
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if (instruction == "-") {
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tape.decrement();
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}
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if (instruction == ".") {
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asciiOut(tape.current.data);
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}
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if (instruction == ",") {
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}
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if (instruction == "[" and tape.current.data < 0.0001) {
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instruction = read(this.bfpath);
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var bracketCount = 1;
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while (bracketCount > 0 and instruction != nil) {
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if (instruction == "[") { bracketCount = bracketCount + 1; }
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if (instruction == "]") { bracketCount = bracketCount - 1; }
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if (bracketCount > 0) { instruction = read(this.bfpath); }
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}
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}
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if (instruction == "]" and tape.current.data >= 0.0001) {
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instruction = read(this.bfpath, true);
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var bracketCount = 1;
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while (bracketCount > 0 and instruction != nil) {
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if (instruction == "]") { bracketCount = bracketCount + 1; }
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if (instruction == "[") { bracketCount = bracketCount - 1; }
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if (bracketCount > 0) { instruction = read(this.bfpath, true); }
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}
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}
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instruction = read(this.bfpath);
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}
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}
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}
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var interpreter = Interpreter("bf/helloworld.bf");
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interpreter.run();
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