SCL is now partially implemented

1 files changed, 501 insertions, 0 deletions

diff --git a/dice-lang/src/bjc/dicelang/scl/StreamControlEngine.java b/dice-lang/src/bjc/dicelang/scl/StreamControlEngine.java
new file mode 100644
index 0000000..fff8b3e
--- /dev/null
+++ b/dice-lang/src/bjc/dicelang/scl/StreamControlEngine.java
@@ -0,0 +1,501 @@
+package bjc.dicelang.scl;
+
+import bjc.dicelang.DoubleMatcher;
+import bjc.dicelang.Errors;
+
+import bjc.utils.esodata.Stack;
+import bjc.utils.esodata.Tape;
+import bjc.utils.funcdata.IList;
+import bjc.utils.funcdata.FunctionalList;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.regex.Pattern;
+
+import static bjc.dicelang.Errors.ErrorKey.*;
+import static bjc.dicelang.scl.StreamControlEngine.Token.Type.*;
+
+/**
+ * Runs a Stream Control Language (SCL) program.
+ *
+ * SCL is a stack-based concatenative language based mostly off of Postscript
+ * and Factor, with inspiration from various other languages.
+ */
+public class StreamControlEngine {
+	static class Token {
+		public static enum Type {
+			/*
+			 * Natural tokens.
+			 * These come directly from strings
+			 */
+			ILIT,     FLIT,  BLIT,
+			SQUOTE,   DQUOTE,
+			OBRACKET, OBRACE,
+			SYMBOL,   WORD,
+
+			/*
+			 * Synthetic tokens.
+			 * These are produced from special tokens.
+			 */
+			SLIT,
+			WORDS, ARRAY,
+
+			/*
+			 * Word tokens
+			 * These are subordinate to WORD tokens
+			 */
+			/*
+			 * Array manipulation
+			 */
+			MAKEARRAY,
+			MAKEEXEC,   MAKEUNEXEC,
+			/*
+			 * Stream manipulation
+			 */
+			NEWSTREAM,
+			LEFTSTREAM, RIGHTSTREAM,
+			DELETESTREAM, MERGESTREAM,
+			/*
+			 * Stack manipulation
+			 */
+			STACKCOUNT, STACKEMPTY,
+			DROP,       NDROP,
+			NIP,        NNIP,
+		}
+
+		/*
+		 * The type of this token
+		 */
+		public Type type;
+
+		/*
+		 * Used for
+		 * 	ILIT
+		 */
+		public long intVal;
+		/*
+		 * Used for
+		 * 	FLIT
+		 */
+		public double floatVal;
+		/*
+		 * Used for
+		 * 	BLIT
+		 */
+		public boolean boolVal;
+		/*
+		 * Used for
+		 * 	SYMBOL
+		 * 	SLIT
+		 */
+		public String stringVal;
+		/*
+		 * Used for
+		 * 	WORD
+		 */
+		public Token tokenVal;
+		/*
+		 * Used for
+		 * 	WORDS
+		 * 	ARRAY
+		 */
+		public IList<Token> tokenVals;
+
+		public Token(Type typ) {
+			type = typ;
+		}
+
+		public Token(Type typ, long iVal) {
+			this(typ);
+
+			intVal = iVal;
+		}
+
+		public Token(Type typ, double dVal) {
+			this(typ);
+
+			floatVal = dVal;
+		}
+
+		public Token(Type typ, boolean bVal) {
+			this(typ);
+
+			boolVal = bVal;
+		}
+
+		public Token(Type typ, String sVal) {
+			this(typ);
+
+			stringVal = sVal;
+		}
+
+		public Token(Type typ, Token tVal) {
+			this(typ);
+
+			tokenVal = tVal;
+		}
+
+		public Token(Type typ, Token.Type tVal) {
+			this(typ, new Token(tVal));
+		}
+
+
+		public Token(Type typ, IList<Token> tVals) {
+			this(typ);
+
+			tokenVals = tVals;
+		}
+
+		public static Token tokenizeString(String token) {
+			if(litTokens.containsKey(token)) {
+				return new Token(litTokens.get(token));
+			} else if(token.startsWith("\\")) {
+				return new Token(SYMBOL, token.substring(1));
+			} else if(builtinWords.containsKey(token)) {
+				return new Token(WORD, builtinWords.get(token));
+			} else if(token.equals("true")) {
+				return new Token(BLIT, true);
+			} else if(token.equals("false")) {
+				return new Token(BLIT, false);
+			} else if(intLitPattern.matcher(token).matches()) {
+				return new Token(ILIT, Long.parseLong(token));
+			} else if(DoubleMatcher.floatingLiteral.matcher(token).matches()) {
+				return new Token(FLIT, Double.parseDouble(token));
+			} else {
+				Errors.inst.printError(EK_SCL_INVTOKEN, token);
+				return null;
+			}
+		}
+
+		private static final Pattern intLitPattern = Pattern.compile("\\A[+\\-]?\\d+\\Z");
+
+		private static final Map<String, Token.Type> litTokens;
+		private static final Map<String, Token.Type> builtinWords; 
+
+		static {
+			litTokens = new HashMap<>();
+
+			litTokens.put("'",  SQUOTE);
+			litTokens.put("\"", DQUOTE);
+			litTokens.put("[",  OBRACKET);
+			litTokens.put("{", OBRACE);
+
+			builtinWords = new HashMap<>();
+
+			builtinWords.put("makearray", MAKEARRAY);
+			builtinWords.put("+stream",   NEWSTREAM);
+			builtinWords.put(">stream",   LEFTSTREAM);
+			builtinWords.put("<stream",   RIGHTSTREAM);
+			builtinWords.put("-stream",   DELETESTREAM);
+			builtinWords.put("<-stream",   MERGESTREAM);
+			builtinWords.put("cvx",       MAKEEXEC);
+			builtinWords.put("cvux",      MAKEUNEXEC);
+			builtinWords.put("#",         STACKCOUNT);
+			builtinWords.put("empty?",    STACKEMPTY);
+			builtinWords.put("drop",      DROP);
+			builtinWords.put("ndrop",     NDROP);
+			builtinWords.put("nip",       NIP);
+			builtinWords.put("nnip",      NNIP);
+		}
+	}
+
+	private StreamEngine eng;
+
+	private Stack<Token> curStack;
+
+	private Map<String, Token> words;
+
+	public StreamControlEngine(StreamEngine eng) {
+		this.eng = eng;
+
+		words = new HashMap<>();
+	}
+
+	/**
+	 * Run a SCL program.
+	 *
+	 * @param tokens The program to run
+	 *
+	 * @return Whether the program executed succesfully
+	 */
+	public boolean runProgram(String[] tokens) {
+		for(int i = 0; i < tokens.length; i++) {
+			String token = tokens[i];
+			Token tok = Token.tokenizeString(token);
+			
+			if(tok == null) {
+				return false;
+			}
+
+			switch(tok.type) {
+			case SQUOTE:
+				i = handleSingleQuote(i, tokens);
+				if(i == -1) return false;
+				break;
+			case OBRACKET:
+				i = handleDelim(i, tokens, "]");
+				if(i == -1) return false;
+				break;
+			case OBRACE:
+				i = handleDelim(i, tokens, "}");
+				if(i == -1) return false;
+				Token brak = curStack.pop();
+				curStack.push(new Token(ARRAY, brak.tokenVals));
+				break;
+			case WORD:
+				handleWord(tok);
+				break;
+			default:
+				curStack.push(tok);
+				break;
+			}
+		}
+
+		return true;
+	}
+
+	private boolean handleWord(Token tk) {
+		boolean succ = true;
+
+		switch(tk.tokenVal.type) {
+		case NEWSTREAM:
+			eng.newStream();
+			break;
+		case LEFTSTREAM:
+			succ = eng.leftStream();
+			if(!succ) return false;
+			break;
+		case RIGHTSTREAM:
+			succ = eng.rightStream();
+			if(!succ) return false;
+			break;
+		case DELETESTREAM:
+			succ = eng.deleteStream();
+			if(!succ) return false;
+			break;
+		case MERGESTREAM:
+			succ = eng.mergeStream();
+			if(!succ) return false;
+			break;
+		case MAKEARRAY:
+			succ = makeArray();
+			if(!succ) return false;
+			break;
+		case MAKEEXEC:
+			succ = toggleExec(true);
+			if(!succ) return false;
+			break;
+		case MAKEUNEXEC:
+			succ = toggleExec(false);
+			if(!succ) return false;
+			break;
+		case STACKCOUNT:
+			curStack.push(new Token(ILIT, curStack.size()));
+			break;
+		case STACKEMPTY:
+			curStack.push(new Token(BLIT, curStack.empty()));
+			break;
+		case DROP:
+			if(curStack.size() == 0) {
+				Errors.inst.printError(EK_SCL_SUNDERFLOW, tk.tokenVal.type.toString());
+				return false;
+			}
+			curStack.drop();
+			break;
+		case NDROP:
+			succ = handleNDrop();
+			if(!succ) return false;
+			break;
+		case NIP:
+			if(curStack.size() < 2) {
+				Errors.inst.printError(EK_SCL_SUNDERFLOW, tk.tokenVal.type.toString());
+				return false;
+			}
+			
+			curStack.nip();
+			break;
+		case NNIP:
+			succ = handleNNip();
+			if(!succ) return false;
+			break;
+		default:
+			Errors.inst.printError(EK_SCL_UNWORD, tk.tokenVal.type.toString());
+			return false;
+		}
+
+		return true;
+	}
+
+	private boolean handleNNip() {
+		Token num = curStack.pop();
+
+		if(num.type != ILIT) {
+			Errors.inst.printError(EK_SCL_INVARG, num.type.toString());
+			return false;
+		}
+
+		int n = (int)num.intVal;
+		
+		if(curStack.size() < n) {
+			Errors.inst.printError(EK_SCL_SUNDERFLOW, NNIP.toString());
+			return false;
+		}
+
+		curStack.nip(n);
+		return true;
+	}
+
+	private boolean handleNDrop() {
+		Token num = curStack.pop();
+
+		if(num.type != ILIT) {
+			Errors.inst.printError(EK_SCL_INVARG, num.type.toString());
+			return false;
+		}
+
+		int n = (int)num.intVal;
+		
+		if(curStack.size() < n) {
+			Errors.inst.printError(EK_SCL_SUNDERFLOW, NDROP.toString());
+			return false;
+		}
+
+		curStack.drop(n);
+		return true;
+	}
+
+	private boolean toggleExec(boolean exec) {
+		Token top = curStack.top();
+
+		if(exec) {
+			if(top.type != ARRAY) {
+				Errors.inst.printError(EK_SCL_INVARG, top.toString());
+				return false;
+			}
+
+			top.type = WORDS;
+		} else {
+			if(top.type != WORDS) {
+				Errors.inst.printError(EK_SCL_INVARG, top.toString());
+				return false;
+			}
+
+			top.type = ARRAY;
+		}
+
+		return true;
+	}
+
+	private boolean makeArray() {
+		Token num = curStack.pop();
+
+		if(num.type != ILIT) {
+			Errors.inst.printError(EK_SCL_INVARG, num.type.toString());
+		}
+
+		IList<Token> arr = new FunctionalList<>();
+
+		for(int i = 0; i < num.intVal; i++) {
+			arr.add(curStack.pop());
+		}
+
+		curStack.push(new Token(ARRAY, arr));
+
+		return true;
+	}
+
+	private int handleDelim(int i, String[] tokens, String delim) {
+		IList<Token> toks = new FunctionalList<>();
+
+		int n      = i + 1;
+		if(n >= tokens.length) {
+			Errors.inst.printError(EK_SCL_MMQUOTE);
+			return -1;
+		}
+		String tok = tokens[n];
+
+		while(!tok.equals(delim)) {
+			Token ntok = Token.tokenizeString(tok);
+
+			switch(ntok.type) {
+			case SQUOTE:
+				n = handleSingleQuote(n, tokens);
+				if(n == -1) return -1;
+				toks.add(curStack.pop());
+				break;
+			case OBRACKET:
+				n = handleDelim(n, tokens, "]");
+				if(n == -1) return -1;
+				toks.add(curStack.pop());
+				break;
+			case OBRACE:
+				i = handleDelim(i, tokens, "}");
+				if(i == -1) return -1;
+				Token brak = curStack.pop();
+				toks.add(new Token(ARRAY, brak.tokenVals));
+				break;
+			default:
+				toks.add(ntok);
+			}
+			/*
+			 * Move to the next token
+			 */
+			n  += 1;
+			if(n >= tokens.length) {
+				Errors.inst.printError(EK_SCL_MMQUOTE);
+				return -1;
+			}
+			tok = tokens[n];
+		}
+
+		/*
+		 * Skip the closing bracket
+		 */
+		n += 1;
+
+		curStack.push(new Token(WORDS, toks));
+
+		return n;
+	}
+
+	private int handleSingleQuote(int i, String[] tokens) {
+		StringBuilder sb = new StringBuilder();
+
+		int n      = i + 1;
+		if(n >= tokens.length) {
+			Errors.inst.printError(EK_SCL_MMQUOTE);
+			return -1;
+		}
+		String tok = tokens[n];
+
+		while(!tok.equals("'")) {
+			if(tok.matches("\\\\+'")) {
+				/*
+				 * Handle escaped quotes.
+				 */
+				sb.append(tok.substring(1));
+			} else {
+				sb.append(tok);
+			}
+
+			/*
+			 * Move to the next token
+			 */
+			n  += 1;
+			if(n >= tokens.length) {
+				Errors.inst.printError(EK_SCL_MMQUOTE);
+				return -1;
+			}
+			tok = tokens[n];
+		}
+
+		/*
+		 * Skip the single quote
+		 */
+		n += 1;
+
+		curStack.push(new Token(SLIT, sb.toString()));
+
+		return n;
+	}
+}