When a program crashes you can often see an error code. It's a 3-digit number, usually shown with a frowny face. You can trigger your own error code by calling control.panic(code).

When static type of x is a class C, the dynamic type of x isn't C, and you try to access a field on x or call a method on x, you will get one of the following codes, depending on dynamic type of x.

• 980 - when x is undefined
• 981 - when x is true or false
• 982 - when x is a number
• 983 - when x is a string
• 984 - when x is object of some type
• 985 - when x is a function
• 989 - when x is null

• 907 - a required configuration setting (in config namespace) is missing
• 908 - a required pin was not defined (also in config namespace)
• 910 - memory limit exceeded (only on Linux targets)
• 914 - TypeScript code was called from interrupt service routine
• 915 - heap dumped - the code is waiting for debugger to load the heap

• 020 - out of memory in Codal heap - too many events or fibers
• 021 - out of memory in GC heap - too many objects
• 030 - heap error (memory corruption)
• 040 - null dereference
• 050 - USB error
• 090 - hardware configuration error - likely using wrong pin for SPI/I2C/PWM/etc

You should not see these.

    PANIC_INVALID_BINARY_HEADER = 901,
    PANIC_OUT_OF_BOUNDS = 902,
    PANIC_REF_DELETED = 903,
    PANIC_SIZE = 904,
    PANIC_INVALID_VTABLE = 905,
    PANIC_INTERNAL_ERROR = 906,
    PANIC_INVALID_ARGUMENT = 909,
    PANIC_SCREEN_ERROR = 911,

The error codes in the 800-899 are even more internal:

• 84X - garbage collector errors