If I am loading a model with Model::find($id) and the id is not found it returns null.
This is fine except if I try to chain things.
Model::find($id)->loadAttributes();
Load attributes is going to fail because it’s not a method of null.
The simple solution break it into two lines and check if it’s null before calling loadAttributes or doing a try/catch but I’m curious if there’s another solution I’m not thinking of.
1
If you can’t do method chaining, don’t do method chaining.
$model = Model::find($id);
if ($model === null) {
... // handle error
}
$model->loadAttributes();
That’s probably the least error prone way to do this. If the null-case is to be expected in the normal course of operation, you should not use the exception system to handle this.
PHP 7 adds a null coalescing operator ??, but not a null-propagating method call operator (e.g. ?. in C#). With such an operator, a call $a?->b() might be equivalent to $a === null ? $a->b() : null.
One idiom you might sometimes see is assigning the variable inside the condition:
if (($model = Model::find($id)) !== null) {
$model->loadAttributes();
} else {
... // handle error
}
This style makes more sense in other languages where this would also restrict the scope of the assigned variable to the conditional, and when there is no error handling – if the return value is null, there’s nothing to do.