1 files changed, 79 insertions, 0 deletions
diff --git a/state.cpp b/state.cpp
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+++ b/state.cpp
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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/>.
+ */
+
+#include "state.hpp"
+
+#include <iterator>
+
+Cell State::beyondip() const
+{
+    return dict.read(ip + 1);
+}
+
+void State::pushr(Cell value)
+{
+    if (rsize() == ReturnStackSize)
+        throw;
+    *++rsp = value;
+}
+
+Cell State::popr()
+{
+    if (rsize() == 0)
+        throw;
+    return *rsp--;
+}
+
+void State::push(Cell value)
+{
+    if (size() == DataStackSize)
+        throw;
+    *++dsp = value;
+}
+
+Cell State::pop()
+{
+    if (size() == 0)
+        throw;
+    return *dsp--;
+}
+
+Cell& State::top()
+{
+    if (size() == 0)
+        throw;
+    return *dsp;
+}
+
+Cell& State::pick(std::size_t i)
+{
+    if (i >= size())
+        throw;
+    return *(dsp - i);
+}
+
+std::size_t State::size() const noexcept
+{
+    return std::distance(dstack, static_cast<const Cell *>(dsp)) + 1;
+}
+
+std::size_t State::rsize() const noexcept
+{
+    return std::distance(rstack, static_cast<const Cell *>(rsp)) + 1;
+}
+