chore(examples): New example for LUA bindings

4 files changed, 124 insertions, 0 deletions

diff --git a/examples/scripting/lua/README.md b/examples/scripting/lua/README.md
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+++ b/examples/scripting/lua/README.md
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+# Lua Scripting with Zen-C
+
+This examples demonstrates how to build your Zen-C application with Lua C bindings,<br>
+and how you can call Lua code from Zen-C (.zc) context, or exposed Zen-C functions from Lua (.lua) context.
+
+> Lua is a powerful, efficient, lightweight, embeddable scripting language, often used in games.
+
+---
+
+Example output:
+
+![alt text](https://i.imgur.com/5vfGuVg.png)
+
+## Setup
+
+Get Lua 5.4 headers and lib:
+
+```sh
+./deps.sh
+```
+
+This will leave the headers (.h) and lib (.a) inside a folder called ``lua``.
+
+## Build
+
+```sh
+zc build lua.zc -o lua
+```
+
+## Run
+
+Either
+
+```sh
+zc run lua.zc
+```
+
+or (after compilation)
+
+```sh
+./lua
+```
+
+## Documentation
+
+- https://www.lua.org/manual/5.4/manual.html
diff --git a/examples/scripting/lua/deps.sh b/examples/scripting/lua/deps.sh
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+++ b/examples/scripting/lua/deps.sh
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+#!/bin/bash
+
+## Downloads lua-5.4.2 headers (.h) and lib (.a) into ./lua
+
+wget "https://sourceforge.net/projects/luabinaries/files/5.4.2/Linux%20Libraries/lua-5.4.2_Linux54_64_lib.tar.gz"
+
+[[ -d "lua" ]] && rm -rf lua
+mkdir -p lua
+
+tar -xf lua-5.4.2_Linux54_64_lib.tar.gz
+
+mv include/* *.a lua/
+rm -rf *.so include lua-5.4.2_Linux54_64_lib.tar.gz
diff --git a/examples/scripting/lua/lua.zc b/examples/scripting/lua/lua.zc
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+++ b/examples/scripting/lua/lua.zc
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+//> include: ./lua
+//> lib: ./lua
+//> link: -Wl,-Bstatic -llua54 -Wl,-Bdynamic -lm -ldl
+//> cflags: -Ofast
+
+import "lua.h";
+import "lauxlib.h";
+import "lualib.h";
+
+fn l_zenc_hello(L: lua_State*) -> int {
+    const name: string = (string)luaL_optstring(L, 1, "world");
+    println "hello from Zen-C, {name}"
+    return 0;
+}
+
+fn main() {
+    var L: lua_State* = luaL_newstate();
+
+    if (!L) return !"Could not initialize LUA.";
+
+    // Opens standard libs
+    luaL_openlibs(L);
+    defer lua_close(L);
+
+    // Expose a Zen-C function to Lua as global "zenc_hello"
+    lua_pushcfunction(L, l_zenc_hello);
+    lua_setglobal(L, "zenc_hello");
+
+    // Run some Lua from a Zen-C variable
+    const script = "print('hello from lua')\nzenc_hello('test')\n";
+
+    if (luaL_dostring(L, script) != LUA_OK) {
+        const err: string = (string)lua_tostring(L, -1);
+        !"lua error: {err}"
+        lua_pop(L, 1);
+    }
+
+    // Run some Lua from a script file
+    if (luaL_loadfile(L, "script.lua") != LUA_OK) {
+        const err: string = (string)lua_tostring(L, -1);
+        !"lua load-error: {err}"
+        lua_pop(L, 1);
+    } else if (lua_pcall(L, 0, 0, 0) != LUA_OK) {
+         const err: string = (string)lua_tostring(L, -1);
+        !"lua error: {err}"
+        lua_pop(L, 1);
+    }
+}
diff --git a/examples/scripting/lua/script.lua b/examples/scripting/lua/script.lua
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+++ b/examples/scripting/lua/script.lua
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+print('hello from lua (script file)')
+
+zenc_hello('test2')
+
+local tbl = {
+    ["something"] = "good",
+    [2] = 3
+}
+
+for k,v in pairs(tbl) do
+    print("Key: "..k.." | Val: "..v)
+end
+
+local str = "4"
+print(tonumber(str))
+
+print(os.date("today is %A, in %B"))