test the code in phasers doc.

Part of #1387

Author: coke

doc/Language/phasers.pod6

@@ -19,6 +19,7 @@ them respond to various control exceptions and exit values.
 
 Here is a summary:
 
+=begin code :skip-test
       BEGIN {...} #  * at compile time, ASAP, only ever runs once
       CHECK {...} #  * at compile time, ALAP, only ever runs once
        INIT {...} #  * at run time, ASAP, only ever runs once
@@ -44,19 +45,20 @@ Here is a summary:
 
     COMPOSE {...} #  when a role is composed into a class
     CLOSE   {...} #  appears in a supply block, called when the supply is closed
+=end code
 
 Phasers marked with a C<*> have a run-time value, and if evaluated earlier than
 their surrounding expression, they simply save their result for use in the
 expression later when the rest of the expression is evaluated:
 
     my $compiletime = BEGIN { now };
-    our $temphandle = ENTER { maketemp() };
+    our $random = ENTER { rand };
 
 As with other statement prefixes, these value-producing constructs may be
 placed in front of either a block or a statement:
 
     my $compiletime = BEGIN now;
-    our $temphandle = ENTER maketemp();
+    our $random = ENTER rand;
 
 Most of these phasers will take either a block or a function reference. The
 statement form can be particularly useful to expose a lexically scoped
@@ -67,12 +69,11 @@ These declare the same variables with the same scope as the preceding example,
 but run the statements as a whole at the indicated time:
 
     BEGIN my $compiletime = now;
-    ENTER our $temphandle = maketemp();
+    ENTER our $random = rand;
 
 (Note, however, that the value of a variable calculated at compile time may not
 persist under run-time cloning of any surrounding closure.)
 
-
 Most of the non-value-producing phasers may also be so used:
 
     END say my $accumulator;
@@ -117,55 +118,66 @@ teardown usually want to happen in the opposite order from each other.
 
 =head2 Execution Order
 
-    Compilation Begins
+Compilation Begins
 
+=for code :skip-test
       BEGIN {...} #  at compile time, ASAP, only ever runs once
       CHECK {...} #  at compile time, ALAP, only ever runs once
     COMPOSE {...} #  when a role is composed into a class
 
-    Execution Begins
+Execution Begins
 
+=for code :skip-test
        INIT {...} #  at run time, ASAP, only ever runs once
 
-    Before block execution begins
+Before block execution begins
 
+=for code :skip-test
         PRE {...} #  assert precondition at every block entry, before ENTER
 
-    Loop execution begins
+Loop execution begins
 
+=for code :skip-test
       FIRST {...} #  at loop initialization time, before any ENTER
 
-    Block execution begins
+Block execution begins
 
+=for code :skip-test
       ENTER {...} #  at every block entry time, repeats on loop blocks.
 
-    Exception maybe happens
+Exception maybe happens
 
+=for code :skip-test
       CATCH {...} #  catch exceptions, before LEAVE
     CONTROL {...} #  catch control exceptions, before LEAVE
 
-    End of loop, either continuing or finished
+End of loop, either continuing or finished
 
+=for code :skip-test
        NEXT {...} #  at loop continuation time, before any LEAVE
        LAST {...} #  at loop termination time, after any LEAVE
 
-    End of block
+End of block
 
+=for code :skip-test
       LEAVE {...} #  at every block exit time (even stack unwinds from exceptions)
        KEEP {...} #  at every successful block exit, part of LEAVE queue
        UNDO {...} #  at every unsuccessful block exit, part of LEAVE queue
 
-    Postcondition for block
+Postcondition for block
 
+=for code :skip-test
        POST {...} #  assert postcondition at every block exit, after LEAVE
 
-    Async whenever-block is complete
+Async whenever-block is complete
 
+=for code :skip-test
        LAST {...} #  if ended normally with done, runs once after block
        QUIT {...} #  catch async exceptions
 
-    Program terminating
+Program terminating
 
+=for code :skip-test
         END {...} #  at run time, ALAP, only ever runs once
 
 =head1 Program Execution Phasers

xt/examples-compilation.t

@@ -29,7 +29,6 @@ if @*ARGS {
             doc/Language/5to6-perlfunc.pod6
             doc/Language/5to6-perlop.pod6
             doc/Language/modules.pod6
-            doc/Language/phasers.pod6
             doc/Language/pod.pod6
             doc/Language/tables.pod6
          >);