---

4.2.6.2 Limiting The Scope Of Errors

When error occurs, the aime interpreters terminate the execution of the defined execution scopes, starting with the most local scope (the instruction) and endind with to the most general, or global scope (the program).

The error propagation down the scopes stack does not need to reach the global scope, and provided the right mechanics are in place, it may be stopped before the program execution is terminated.

A C interface trivial method of trapping errors is ignoring the error returns of functions executed via function pointers in application defined functions.

See Step By Step Higher Order Function Execution.

Care must be taken not to ignore the unrecoverable errors, though.

The trap library objects export a number of interfaces concerned with error trapping. They execute functions and trap the errors that are not indicated as being serious enough to prompt program execution termination.

See Trap Library.

Most of the applicable libaime interfaces return one of error class indications when in error.

See Error Classes.

The C interfaces that make subject to error trapping and thus have their returns examined for error classification include function implementing:

• aime functions

  See Functions.

  See struct x1f4_function_type.

• aime operators

  See Prefix Unary Operators.

  See Infix Binary Operators.

  See struct x1f4_operator_type.

• the control returning method of the procedural step by step higher order function execution mechanism

  See struct x1f4_dispatch_type.

  See Step By Step Higher Order Function Execution.

• the method some program execution routines execute after successful expression evaluations

  See x1f4_long_program.

  See x1f4_note_program.

  See x1f4_long_shuffle.

  See x1f4_note_shuffle.

See Error Trapping Examples.