The error handler module defines what happens when certain types of errors occur.
undefined_function(Module, Func, ArgList) -> term()
Module = Func = atom()
ArgList = [term()]
This function is evaluated if a call is made to
Module:Func(ArgList)
which is undefined. This function
is evaluated inside the process making the original call.
If Module
is interpreted, the interpreter is invoked
and the return value of the interpreted Func(ArgList)
call is returned.
Otherwise, it returns, if possible, the value of
apply(Module, Func, ArgList)
after an attempt has been
made to autoload Module
. If this is not possible, the
function calling Module:Func(ArgList)
is exited.
undefined_lambda(Module, Fun, ArgList) -> term()
Module = Func = atom()
ArgList = [term()]
This function is evaluated if a call is made to
Fun(ArgList)
when the module defining the fun
is not loaded.
This function is evaluated inside the process making the original call.
If Module
is interpreted, the interpreter is invoked
and the return value of the interpreted Fun(ArgList)
call is returned.
Otherwise, it returns, if possible, the value of
apply(Fun, ArgList)
after an attempt has been
made to autoload Module
. If this is not possible, the
process calling the fun
is exited.
The code in error_handler
is complex and should not be
changed without fully understanding the interaction between the
error handler, the init
process of the code server, and the
I/O mechanism of the code.
Changes in the code which may seem small can cause a deadlock
as unforeseen consequences may occur. The use of input
is
dangerous in this type of code.