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+/**
+ * Alee Forth: A portable and concise Forth implementation in modern C++.
+ * Copyright (C) 2023  Clyne Sullivan <clyne@bitgloo.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#ifndef ALEEFORTH_PARSER_HPP
+#define ALEEFORTH_PARSER_HPP
+
+#include "executor.hpp"
+
+class Parser
+{
+public:
+    ParseStatus parse(State& state, std::string_view& str) {
+        const auto end = str.find_first_of(" \t\n\r");
+	const auto sub = str.substr(0, end);
+
+	if (state.pass != Pass::None) {
+	    switch (state.pass) {
+	    case Pass::Comment:
+                if (str.front() == ')')
+	            state.pass = Pass::None;
+
+	        str = str.substr(1);
+		break;
+	    case Pass::Colon:
+		state.pass = Pass::None;
+                state.compiling = true;
+		state.dict.addDefinition(sub);
+		break;
+	    case Pass::Constant:
+		state.pass = Pass::None;
+                state.compiling = true;
+		state.dict.addDefinition(sub);
+		state.dict.add(CoreWords::HiddenWordLiteral);
+		state.dict.add(state.pop());
+                state.dict.add(CoreWords::findi("exit"));
+                break;
+	    default:
+		break;
+	    }
+	} else {
+	    if (auto i = CoreWords::findi(sub); i >= 0) {
+		if (state.compiling)
+                    state.dict.add(i);
+		if (!state.compiling || sub.front() == ';')
+	            CoreWords::run(i, state);
+	    } else if (auto j = state.dict.find(sub); j > 0) {
+		auto e = state.dict.getexec(j);
+	        if (state.compiling) {
+		    if (state.dict.read(j) & CoreWords::Immediate) {
+		        state.compiling = false;
+	    	        Executor::fullexec(state, e);
+		        state.compiling = true;
+		    } else {
+		        state.dict.add(CoreWords::HiddenWordJump);
+	    	        state.dict.add(e);
+		    }
+		} else {
+	    	    Executor::fullexec(state, e);
+		}
+	    } else {
+	        char *p;
+	        const auto l = static_cast<Cell>(std::strtol(sub.data(), &p, 10));
+
+	        if (p != sub.data()) {
+	    	    if (state.compiling) {
+		        state.dict.add(CoreWords::HiddenWordLiteral);
+		        state.dict.add(l);
+		    } else {
+	                state.push(l);
+		    }
+	        } else {
+	            return ParseStatus::Error;
+	        }
+	    }
+
+	    if (end == std::string_view::npos)
+                return ParseStatus::Finished;
+        }
+
+	const auto next = str.find_first_not_of(" \t\n\r", end);
+
+	if (next == std::string_view::npos) {
+            return ParseStatus::Finished;
+	} else {
+	    str = str.substr(next);
+	    return ParseStatus::Continue;
+	}
+    }
+};
+
+#endif // ALEEFORTH_PARSER_HPP
+