Question

Is there a performance penalty to accessing a constant within a namespace that was defined outside the namespace WITHOUT using the \ namespace trigger?

ie. Is echo MYCONSTANT slower than echo \MYCONSTANT ?

Answer 1

Silly microptimizations are silly. If you want to optimize anything, then use the frigging profiler and look at a shiny graph that gives relevant results for the whole application. Optimizing the tiniest pieces makes no sense, when it’s SQL queries and loops that are slowing down the application.

I’m just giving you a list because it puts namespaced code in a bad light. Also, very unscientific. Can’t be bothered to run 100 tests.

                          PHP 5.3            PHP 5.4

 CONSTI in global scope    1.69s              2.02s
 \CONSTI in global scope   1.87s              2.20s
 CONSTI in namespace       2.01s              2.25s
 \CONSTI in namespace      1.87s (varying)    2.13s   (for 1M runs)

Only run with PHP 5.3. And the minuscle differences are probably from the parser/tokenizer. Not factual runtime performance discrepancies.