Panic in OpenSCAD

In OpenSCAD, there isn’t a direct equivalent to panic or exception handling. However, we can demonstrate a similar concept using assert() and error messages. Here’s an example:

// This function simulates a condition that might cause a panic
function problematic_function() = 
    let(condition = false)
    assert(condition, "A problem occurred");

// This function simulates file creation
function create_file(filename) = 
    let(success = false)
    assert(success, str("Failed to create file: ", filename));

// Main program
function main() = 
    let(
        // This will cause an assertion failure, similar to a panic
        _ = problematic_function(),
        
        // This would also cause an assertion failure if reached
        _ = create_file("/tmp/file")
    )
    undef;

// Run the main function
main();

In OpenSCAD, we use assert() to check for conditions that should always be true. If the condition is false, OpenSCAD will halt execution and display an error message. This is somewhat similar to how panic works in other languages.

When you run this program, it will halt execution at the first assert() that fails, which is in the problematic_function(). The error message will be displayed, and the program will not continue to the file creation part.

To see the program try to create a temp file, you could comment out the first assert() in the main() function.

Running this program in OpenSCAD will result in an error message similar to this:

ERROR: Assertion 'A problem occurred' failed in file <stdin>, line 4

Note that unlike some languages which use exceptions for handling of many errors, in OpenSCAD we typically use assertion checks and error messages for debugging and development. For production code, you would typically handle errors more gracefully, perhaps by returning special values or using optional return types.

Remember that OpenSCAD is primarily a 3D modeling scripting language, so its error handling and program flow control are quite different from general-purpose programming languages. The concepts of panics and recoveries don’t directly apply, but we can achieve similar debugging and error reporting functionality using assertions and error messages.