Errors and exceptions

In PHP7, most errors are now reported as error exceptions. Only a few fatal errors halt script execution; otherwise, if you are carrying out error or exception handling, it will not halt the script. This is because now the Errors class implements a Throwable interface just like the Exception class, which also implements Throwable. So now, in most cases, fatal errors can be avoided through exception handling.

Here are some sub-classes of the error class:

• TypeError
• ParseError
• ArithmeticError
  • DivisionByZeroError
• AssertionError

This is how you can simply catch an error and handle it:

try {
    fn();
} catch(Throwable $error){
    echo $error->getMessage(); //Call to undefined function fn()
}

Here, $error->getMessage() is a method that is actually returning this message as a string. In our preceding example, the message will be similar to this: Call to undefined function fn().

This is not the only method you can use. Here is a list of methods that are defined in the Throwable interface; you can use them accordingly during error/exception handling. After all, the Exception and Error classes both implement the same Throwable interface:

interface Throwable
{
    public function getMessage(): string;
    public function getCode(): int;
    public function getFile(): string;
    public function getLine(): int;
    public function getTrace(): array;
    public function getTraceAsString(): string;
    public function getPrevious(): Throwable;
    public function __toString(): string;
}