There doesn't seem to be a way to store constants that have already been defined. This function, apc_define_constants(), does both things: (1) defines a constant, and (2) stores the constant in the cache. This is unfortunate, since it introduces the requirement to handle constant definitions differently when APC is not available.
(If this function had a "$do_not_define" parameter, or the like, that would give it more flexibility. I suppose filing a bug report would be a step in the right direction to getting this idea considered.)
(PECL apc >= 3.0.0)
apc_load_constants — Loads a set of constants from the cache
$case_sensitive= true ] )
Loads a set of constants from the cache.
The name of the constant set (that was stored with apc_define_constants()) to be retrieved.
The default behaviour for constants is to be declared case-sensitive; i.e. CONSTANT and Constant represent different values. If this parameter evaluates to
FALSEthe constants will be declared as case-insensitive symbols.
TRUE on success or
FALSE on failure.
Example #1 apc_load_constants() example
$constants = array(
'ONE' => 1,
'TWO' => 2,
'THREE' => 3,
echo ONE, TWO, THREE;
The above example will output: