| In addition to running Parrot bytecode on the command line, you can also load precompiled bytecode directly into your PASM source file. The load_bytecode opcode takes a single argument: the name of the bytecode file to load. So, if you create a file named file.pasm containing a single subroutine: # file.pasm .pcc_sub _sub2: # .pcc_sub stores a global sub print "in sub2\n" invoke P1
and compile it to bytecode using the -o command-line switch: $ parrot -o file.pbc file.pasm
You can then load the compiled bytecode into main.pasm and directly call the subroutine defined in file.pasm : # main.pasm _main: load_bytecode "file.pbc" # compiled file.pasm find_global P0, "_sub2" invokecc end
The load_bytecode opcode also works with source files, as long as Parrot has a compiler registered for that type of file: # main2.pasm _main: load_bytecode "file.pasm" # PASM source code find_global P0, "_sub2" invokecc end
Subroutines marked with @LOAD run as soon as they're loaded (before load_bytecode returns), rather than waiting to be called. A subroutine marked with @MAIN will always run first, no matter what name you give it or where you define it in the file. # file3.pasm .pcc_sub @LOAD _entry: # mark the sub as to be run print "file3\n" invoke P1 # return # main3.pasm _first: # first is never invoked print "never\n" invoke P1 .pcc_sub @MAIN _main: # because _main is marked as the print "main\n" # MAIN entry of program execution load_bytecode "file3.pasm" print "back\n" end
This example uses both @LOAD and @MAIN . Because the _main subroutine is defined with @MAIN it will execute first even though another subroutine comes before it in the file. _main prints a line, loads the PASM source file, and then prints another line. Because _entry in file3.pasm is marked with @LOAD it runs before load_bytecode returns, so the final output is: main file3 back
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