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Programming-Idioms

# 89 Handle invalid argument
You've detected that the integer value of argument x passed to the current function is invalid. Write the idiomatic way to abort the function execution and signal the problem.
New implementation

Be concise.

Be useful.

All contributions dictatorially edited by webmasters to match personal tastes.

Please do not paste any copyright violating material.

Please try to avoid dependencies to third-party libraries and frameworks.

Other implementations 
enum {
    E_OK,
    E_OUT_OF_RANGE
};

int square(int x, int *result) {
    if (x > 1073741823) {
        return E_OUT_OF_RANGE;
    }
    *result = x*x;
    return E_OK;
}
throw domain_error("oops!");
throw new ArgumentException(nameof(×));
import std.format;
throw new Exception("invalid value for x (%s) in '%s'".format(x, __PRETTY_FUNCTION__));
void foo(int x)
in
{
    assert(x != 0, "wrong value for x");
}
body
{
    // function
}
error(badarg).
  if (x > largest_value) error stop "Illegal value in function."
return nil, fmt.Errorf("invalid value for x: %v", x)
throw new IllegalArgumentException("Invalid value for x: $x")
sqrt' :: Int -> Either String Int
sqrt' x | x < 0 = Left "Invalid argument"
sqrt' x         = Right (sqrt x)
throw new Error('x is invalid');
<T> void f(T x) {
    Objects.requireNonNull(x);
}
<T> void f(T x) throws Exception {
    if (x != value) throw new Exception();
}
void f(int x) {
    Objects.checkIndex(x, 123);
}
throw new IllegalArgumentException("Invalid value for x:" + x);
return nil, "Invalid argument x"
error("Invalid argument x")
throw new \InvalidArgumentException($x . ' is invalid.');
Uses sysutils, math;
Raise EInvalidArgument.CreatFmt('Invalid value: %d',[x]);
die "Invalid argument $x";
raise ValueError("x is invalid")
def check_index(length):
    def f(function):
        def _f(x):
            error(x >= length)
            return function(x)
        return _f
    return f
def require_nonnull(function):
    def f(x):
        error(not x)
        return function(x)
    return f
def error(value):
    if value:
        raise ValueError
@require_nonnull
@check_index(123)
def function(value):
    ...
function(x)
def check_range(start, stop):
    def wrap(f):
        def check(value):
            if not start <= value < stop:
                raise ValueError
            return True
        def wrapper(*args, **kwargs):
            if all(map(check, args)):
                return f(*args, **kwargs)
        return wrapper
    return wrap
@check_range(0, 3.14159)
def function(*args):
    ...
raise ArgumentError, "invalid value #{x}."
enum CustomError { InvalidAnswer }

fn do_stuff(x: i32) -> Result<i32, CustomError> {
    if x != 42 {
        Err(CustomError::InvalidAnswer)
    } else {
        Ok(x)
    }
}

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