Throw/Catch in lua?

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#1

In C++ there are these things called through and catch. Suppose we wanted to do something but wanted to pause the code and run some other thing incase it errored.

#import <iostream>
using namespace std;
int main() {
  string inp;
  while (true) {
    try {
      cout << "Input number: " << endl;
      cin >> inp;
      int out = stoi(inp); --This is like tonumber() for you guys
      cout << to_string(inp) << endl;
      exit(0);
} catch(exception) {
      cout << "Please enter a number." << endl;
}
}
return 0;
}

My question is, is there a way to catch errors and run code like this in lua?

#2

pcall is probably what you’re looking for. Not sure if it’s exactly the same for your use case but it’s similar.

local state, error_message = pcall(function() x += 2 end) --//x is undefined so this will error end)

if not state then --//state is true/false depending on if this protected call ran without error
print(error_message)
end
#3

Does pcall() run code before in the pcall after a line it has errored?

#4

It runs the given function in protected mode, which prevents errors from affecting the thread that called the pcall.

If it errors I believe it’ll stop executing the function at the line of the error, it just won’t affect the main thread at all so it will keep running

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