ErrnoException.enforce

Tries to evaluate expr. If it fails, checks the global errno and uses matching message as base for exception message, as well as throws the exception.

class ErrnoException

void

enforce

(

bool expr

lazy cstring msg

istring name = ""

istring file = __FILE__

int line = __LINE__

)

Parameters

expr bool: expression that returns false upon failure that is expected to set global errno
msg cstring: extra error message to append after main error description, can be empty
name istring: extern function name that is expected to set errno
file istring: file where the expr is evaluated
line int: line where the expr is evaluated

Throws

this if 'expr' is false

Examples

try
{
    (new ErrnoException).enforce(
        { .errno = EMFILE; return false; } (),
        "extra",
        "FUNCTION"
    );
    test(false);
}
catch (ErrnoException e)
{
    test!("==")(e.message(),
                "FUNCTION: Too many open files (extra)"[]);
    test!("==")(e.errorNumber(), EMFILE);
}

ErrnoException.enforce

Parameters

Throws

Examples

Meta

Source