get_debug_type View as Markdown

Proposal

This RFC proposes to add a new function get_debug_type that will return the given type of a variable.

This is to replace the following pattern, which may be used to generate debugging messages when dealing with types which cannot be handled by existing PHP runtime checking based on parameter types, such as those coming from an array.

$bar = $arr['key'];
if (!($bar instanceof Foo)) { 
  // this shows the most simple of patterns, to get the real type an assoc array
  // must be present to convert long-form "integer" into int etc.
  throw new TypeError('Expected ' . Foo::class . ' got ' . (is_object($bar) ? get_class($bar) : gettype($bar)));
}
 
// would become
if (!($bar instanceof Foo)) { 
  throw new TypeError('Expected ' . Foo::class . ' got ' . get_debug_type($bar));
}
 
$bar->someFooMethod();

This function would differ from gettype in that it would return native type names, e.g. “int” rather than “integer” and would automatically resolve class names. The following table shows what get_debug_type() returns for different values, and what gettype() returns for the same value (if it is different):

Backward Incompatible Changes

None

Proposed PHP Version(s)

PHP 8.0

Voting

Vote: Add get_debug_type as described — Yes: 42 · No: 3 (closed)

Implementation

https://github.com/php/php-src/pull/5143

References

Initial discussion @ https://github.com/php/php-src/pull/5143