PHP Sadness

Can't throw exceptions from __toString() functions

Fatal error: (...)::__toString() must not throw an exception in ...

PHP arbitrarily disallows exceptions in __toString functions. (Amusingly, it also just converts them to another exception, destroying the actual error message and making it harder to debug.)

Significance: Missing Features

Language features make developers' lives easier. Often, language features are not complex for the language designers to implement (barring unnecessary complications in the internals), but can save developers hours of time. Missing language features are disrespectful to developers and encourage dirty hacks, "clever" solutions, and kludgy workarounds to achieve the desired functionality.

Significance: Implications for Internals

The mere presence of this issue tends to imply some fatal flaw or unnecessary complexity at the most basic levels of the language. For example, an overly complex parser might be trying to compensate for missing functionality in the interpreter by incorrectly (and misleadingly) validating code at the syntax level, or messages without details could indicate that the internal design prohibits access to values where they should be reachable in a sane implementation.