The current phase of the perl interpreter.
Possible values are:
ThePerlInterpreter* is being constructed viaperl_construct. This value is mostly there for completeness and for use via the underlying C variablePL_phase. It's not really possible for Perl code to be executed unless construction of the interpreter is finished.
This is the global compile-time. That includes, basically, everyBEGIN block executed directly or indirectly from during the compile-time of the top-level program.
This phase is not called "BEGIN" to avoid confusion withBEGIN-blocks, as those are executed during compile-time of any compilation unit, not just the top-level program. A new, localised compile-time entered at run-time, for example by constructs aseval "use SomeModule" are not global interpreter phases, and therefore aren't reflected by${^GLOBAL_PHASE}.
Execution of anyCHECK blocks.
Similar to "CHECK", but forINIT-blocks, notCHECK blocks.
The main run-time, i.e. the execution ofPL_main_root.
Execution of anyEND blocks.
Global destruction.
Also note that there's no value for UNITCHECK-blocks. That's because those are run for each compilation unit individually, and therefore is not a global interpreter phase.
Not every program has to go through each of the possible phases, but transition from one phase to another can only happen in the order described in the above list.
An example of all of the phases Perl code can see:
BEGIN { print "compile-time: ${^GLOBAL_PHASE}\n" }INIT { print "init-time: ${^GLOBAL_PHASE}\n" }CHECK { print "check-time: ${^GLOBAL_PHASE}\n" }{ package Print::Phase; sub new { my ($class, $time) = @_; return bless \$time, $class; } sub DESTROY { my $self = shift; print "$$self: ${^GLOBAL_PHASE}\n"; }}print "run-time: ${^GLOBAL_PHASE}\n";my $runtime = Print::Phase->new( "lexical variables are garbage collected before END");END { print "end-time: ${^GLOBAL_PHASE}\n" }our $destruct = Print::Phase->new( "package variables are garbage collected after END");This will print out
compile-time: STARTcheck-time: CHECKinit-time: INITrun-time: RUNlexical variables are garbage collected before END: RUNend-time: ENDpackage variables are garbage collected after END: DESTRUCTThis variable was added in Perl 5.14.0.
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