58 lines
1.8 KiB
Zig
58 lines
1.8 KiB
Zig
//! Simple Lua interpreter
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//! This is a modified program from Programming in Lua 4th Edition
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const std = @import("std");
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// The ziglua module is made available in build.zig
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const ziglua = @import("ziglua");
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pub fn main() anyerror!void {
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var gpa = std.heap.GeneralPurposeAllocator(.{}){};
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const allocator = gpa.allocator();
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defer _ = gpa.deinit();
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// Initialize The Lua vm and get a reference to the main thread
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var lua = try ziglua.Lua.init(allocator);
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defer lua.deinit();
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// Open all Lua standard libraries
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lua.openLibs();
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var stdin = std.io.getStdIn().reader();
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var stdout = std.io.getStdOut().writer();
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var buffer: [256]u8 = undefined;
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while (true) {
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_ = try stdout.write("> ");
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// Read a line of input
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const len = try stdin.read(&buffer);
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if (len == 0) break; // EOF
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if (len >= buffer.len - 1) {
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try stdout.print("error: line too long!\n", .{});
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continue;
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}
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// Ensure the buffer is null-terminated so the Lua API can read the length
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buffer[len] = 0;
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// Compile a line of Lua code
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lua.loadString(buffer[0..len :0]) catch {
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// If there was an error, Lua will place an error string on the top of the stack.
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// Here we print out the string to inform the user of the issue.
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try stdout.print("{s}\n", .{lua.toString(-1) catch unreachable});
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// Remove the error from the stack and go back to the prompt
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lua.pop(1);
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continue;
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};
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// Execute a line of Lua code
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lua.protectedCall(0, 0, 0) catch {
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// Error handling here is the same as above.
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try stdout.print("{s}\n", .{lua.toString(-1) catch unreachable});
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lua.pop(1);
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};
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}
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}
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