>>>>> "ST" == Sam Tregar <[EMAIL PROTECTED]> writes:
>> * Integer, String, and Number registers 0-x are used to pass parameters
>> when the compiler calls routines.
ST> s/compiler/interpreter/, right?
nope. he means when the compiler generates op codes. the compiler will
generate code to put the op code params in registers (this is done with
other op codes). then the interpreter will get an op code and fetch the
registers and actually call the op code function via the vtable.
it is tricky to keep track of what the compiler does and generates and
then what the interpreter sees and does.
>> * Subs may have variable number, or unknown number, of PMC parameters.
>> (Basically Parrot variables) They may *not* take a variable or unknown
>> number of integer, string, or number parameters.
ST> I don't understand this restriction. Won't it make implementing
ST> variadic functions more difficult?
nope. that would be handled by multiple dispatch. it will compare the
subprototypes and call the best/right sub. someone else said that we
could do it just as easily for regular subs as for methods.
for variable list of args, then either all the args are in one list
which is passed (by ref) in register 0. or if the sub has a prototype
with the last arg being an array (which will slurp all the rest of the
args) then that param will be an array ref and get the rest as a single
list. this is so all calls will have a known and fixed number of args at
the opcode level.
uri
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Uri Guttman --------- [EMAIL PROTECTED] ---------- http://www.sysarch.com
SYStems ARCHitecture and Stem Development ------ http://www.stemsystems.com
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