xref: /freebsd/contrib/lutok/examples/interpreter.cpp (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
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28 
29 /// \file examples/interpreter.cpp
30 /// Implementation of a basic command-line Lua interpreter.
31 
32 #include <cstdlib>
33 #include <iostream>
34 #include <string>
35 
36 #include <lutok/exceptions.hpp>
37 #include <lutok/operations.hpp>
38 #include <lutok/state.ipp>
39 
40 
41 /// Executes a Lua statement provided by the user with error checking.
42 ///
43 /// \param state The Lua state in which to process the statement.
44 /// \param line The textual statement provided by the user.
45 static void
46 run_statement(lutok::state& state, const std::string& line)
47 {
48     try {
49         // This utility function allows us to feed a given piece of Lua code to
50         // the interpreter and process it.  The piece of code can include
51         // multiple statements separated by a semicolon or by a newline
52         // character.
53         lutok::do_string(state, line, 0, 0, 0);
54     } catch (const lutok::error& error) {
55         std::cerr << "ERROR: " << error.what() << '\n';
56     }
57 }
58 
59 
60 /// Program's entry point.
61 ///
62 /// \return A system exit code.
63 int
64 main(void)
65 {
66     // Create a new session and load some standard libraries.
67     lutok::state state;
68     state.open_base();
69     state.open_string();
70     state.open_table();
71 
72     for (;;) {
73         std::cout << "lua> ";
74         std::cout.flush();
75 
76         std::string line;
77         if (!std::getline(std::cin, line).good())
78             break;
79         run_statement(state, line);
80     }
81 
82     return EXIT_SUCCESS;
83 }
84