Jerome Vouillon:
# I propose the following alternate guidelines.
#
# First, the code would look something like this:
#
# STRING * concat (STRING* a, STRING* b, STRING* c) {
# PARROT_start();
# PARROT_str_params_3(a, b, c);
# PARROT_str_local_2(d, e);
#
# d = string_concat(a, b);
# e = string_concat(d, c);
#
# PARROT_return(e);
# }
#
# Then, the rules would be:
# (1) start your functions with PARROT_start
# (2) register all parameters of type STRING * with PARROT_str_params
# (2') register all parameters of type PMC * with PARROT_pmc_params
# (3) declare the local variables of type STRING * with
# PARROT_str_local
# (3') declare the local variables of type PMC * with PARROT_pmc_local
I assume the lack of mentions of Buffers are an oversight.
# (4) use PARROT_return to exit the function
# (5) do not nest function calls
# (for instance, "e = string_concat (string_concat(a, b), c);"
# would be forbidden)
I don't understand the reasoning behind (5). Would you care to
elaborate?
# The idea is to explicitly manage a stack of parrot objects,
# which can be traversed by the GC.
#
# This rules let a lot of freedom to the garbage collector:
# - it can garbage collect anything which is not rooted;
# - it can move objects (strings and PMCs) around;
# - objects do not need any additional field/flag;
# - exception can be implemented using longjmp; if an exception is
# raised, temporary allocated objects will be properly freed
# by the GC.
Anything that lets us use longjmp is fine by me. ;^)
# Do you think that these rules would be too error-prone, or
# too cumbersome?
May I suggest an alternate version?
STRING * concat (STRING* a, STRING* b, STRING* c) {
Enter_sub(); /* The macros don't really need a Parrot_ prefix, do
they? */
Str_params_3(a, b, c);
Decl_str(d); /* These aren't needed anymore, actually... */
Decl_str(e);
Return(
string_concat(
string_concat(a, b),
c
)
);
}
--Brent Dax <[EMAIL PROTECTED]>
@roles=map {"Parrot $_"} qw(embedding regexen Configure)
blink: Text blinks (alternates between visible and invisible).
Conforming user agents are not required to support this value.
--The W3C CSS-2 Specification
